The role of the epidermis and the mechanism of action of occlusive dressings in scarring

Which Moisturizer to Use in Scar Therapy after Burn Injuries? A Subjective and Objective Skin and Scar Evaluation after Topical Treatment with Dexpanthenol, Aloe Vera, and Plant Oil

Background and Objectives: Good scar management in burn care is essential. Nevertheless, there are no consistent recommendations regarding moisturizers for scar management. Our aim was to investigate and compare the effects of commonly used products on normal skin and burn scars. Materials and Methods: A total of 30 skin-healthy (control group) and 12 patients with burn scars were included in this study. For an intraindividual comparison, each participant received creams consisting of dexpanthenol (P), aloe vera (A), and a natural plant oil (O) with instructions to apply them daily to a previously defined area for at least 28 days. Objective scar evaluation was performed with Visioscan®; Tewameter®; Cutometer®, and the Oxygen To See® device. Subjective evaluation was performed with an "application" questionnaire, the Patient and Observer Scar Assessment Scale (POSAS), and with the "best of three" questionnaire. Results: After (A) a high trend of amelioration of +30%, TEWL was detected on the scar area. Blood flow increased slightly on healthy skin areas after (A) application to +104%. The application of (A) on healthy skin demonstrated a positive effect on the parameters of scaliness (+22%, p < 0.001), softness (+14%, p = 0.046), roughness R1 (+16%, p < 0.001) and R2 (+17%, p = 0.000), volume (+22%, p < 0.001), and surface area (+7%, p < 0.001) within the control group. After (P), a significant improvement of the baseline firmness parameter of +14.7% was detected (p = 0.007). (P) also showed a beneficial effect on the parameters of R1 (+7%, p = 0.003), R2 (+6%, p = 0.001), and volume (+17%, p = 0.001). (O) lead to a statistically significant improvement of volume (+15%, p = 0.009). Overall, most study participants stated (A) to be the "best of three". Conclusions: (A) performed statistically best, and is a well-tolerated moisturizing product. However, further quantitative studies are needed to provide statistically significant clarification for uniform recommendations for scar therapy.

Hypertrophic Scars and Keloids: Advances in Treatment and Review of Established Therapies

Hypertrophic scars and keloids can have significant detrimental effects on patients both psychosocially and functionally. A careful identification of patient risk factors and a comprehensive management plan are necessary to optimize outcomes. Patients with a history of dystrophic scarring should avoid unnecessary procedures and enhance the wound-healing process using various preventive strategies. As there is no single, fully efficacious treatment modality, prevention remains the best approach in reducing aberrant scar formation. When prevention therapies fail, keloids have been shown to be respond to a variety of therapies including topical and injectable corticosteroids, 5-fluorouracil, radiotherapy, lasers, and surgical excision, all with varying efficacies. As such, management should be tailored to the individual patient's risk factors with the use of combination therapies to reduce recurrence rates. Still, keloid and hypertrophic scar therapies are widely diverse with novel treatment modalities providing alternatives for recurring lesions. Laser-assisted drug delivery, skin priming, and novel topical therapies may provide alternative options for the management of hypertrophic scars and keloids.

Silicone gel sheeting for treating keloid scars

BACKGROUND

Keloid scarring is one of the most common types of pathological scarring. Keloid scars that fail to heal can affect a person's physical and psychological function by causing pain, pruritus, contractures, and cosmetic disfigurement. Silicone gel sheeting (SGS) is made from medical-grade silicone reinforced with a silicone membrane backing and is one of the most commonly used treatments for keloid scars. However, there is no up-to-date systematic review assessing the effectiveness of SGS for keloid scars. A clear and rigorous review of current evidence is required to guide clinicians, healthcare managers and people with keloid scarring.

OBJECTIVES

To assess the effectiveness of silicone gel sheeting for the treatment of keloid scars compared with standard care or other therapies.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was December 2021.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that recruited people with any keloid scars and assessed the effectiveness of SGS.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, risk of bias assessment, data extraction and GRADE assessment of the certainty of evidence. We resolved initial disagreements by discussion, or by consulting a third review author when necessary.

MAIN RESULTS

Two studies met the inclusion criteria. Study sample sizes were 16 and 20 participants. The trials were clinically heterogeneous with differences in causes for scarring (e.g. surgery, infected wounds, and trauma), site (e.g. chest and back), and ages of scars. The duration of follow-up was three and four and a half months. The included studies reported three comparisons; SGS compared with no treatment, SGS compared with non-silicone gel sheeting (a dressing similar to SGS but which does not contain silicone), and SGS compared with intralesional injections of triamcinolone acetonide. One trial had a split-body design and one trial had an unclear design (resulting in a mix of paired and clustered data). The included studies reported limited outcome data for the primary review outcome of scar severity measured by health professionals and no data were reported for severity of scar measured by patients or adverse events. For secondary outcomes some data on pain were reported, but health-related quality of life and cost-effectiveness were not reported. Both trials had suboptimal outcome reporting, thus many domains in the risk of bias were assessed as unclear. All evidence was rated as being very low-certainty, mainly due to risk of bias, indirectness, and imprecision.  SGS compared with no treatment Two studies with 33 participants (76 scars) reported the severity of scar assessed by health professionals, and we are uncertain about the effect of SGS on scar severity compared with no treatment (very low-certainty evidence, downgraded once for risk of bias, once for inconsistency, once for indirectness, and once for imprecision). We are uncertain about the effect of SGS on pain compared with no treatment (21 participants with 40 scars; very low-certainty evidence, downgraded once for risk of bias, once for inconsistency, once for indirectness, and once for imprecision). No data were reported for other outcomes including scar severity assessed by patients, adverse events, adherence to treatment, health-related quality of life and cost-effectiveness. SGS compared with non-SGS One study with 16 participants (25 scars) was included in this comparison. We are uncertain about the effect of SGS on scar severity assessed by health professionals compared with non-SGS (very low-certainty evidence, downgraded once for risk of bias, once for indirectness, and once for imprecision). We are also uncertain about the effect of SGS on pain compared with non-SGS (very low-certainty evidence, downgraded once for risk of bias, once for indirectness, and once for imprecision). No data were reported for other outcomes including scar severity assessed by patients, adverse events, adherence to treatment, health-related quality of life and cost-effectiveness. SGS compared with intralesional injections of triamcinolone acetonide One study with 17 participants (51 scars) reported scar severity assessed by health professionals, and we are uncertain about the effect of SGS on scar severity compared with intralesional injections of triamcinolone acetonide (very low-certainty evidence, downgraded once for risk of bias, once for indirectness, and once for imprecision). This study also reported pain assessed by health professionals among 5 participants (15 scars) and we are uncertain about the effect of SGS on pain compared with intralesional injections of triamcinolone acetonide (very low-certainty evidence, downgraded once for risk of bias, once for indirectness, and twice for imprecision). No data were reported for other outcomes including scar severity assessed by patients, adverse events, adherence to treatment, health-related quality of life and cost-effectiveness.

AUTHORS' CONCLUSIONS

There is currently a lack of RCT evidence about the clinical effectiveness of SGS in the treatment of keloid scars. From the two studies identified, there is insufficient evidence to demonstrate whether the use of SGS compared with no treatment, non-SGS, or intralesional injections of triamcinolone acetonide makes any difference in the treatment of keloid scars. Evidence from the included studies is of very low certainty, mainly driven by the risk of bias, indirectness, and imprecision due to small sample size. Further well-designed studies that have good reporting methodologies and address important clinical, quality of life and economic outcomes are required to reduce uncertainty around decision-making in the use of SGS to treat keloid scars.

Vascular and Collagen Target: A Rational Approach to Hypertrophic Scar Management

Significance: Hypertrophic scarring is a challenging issue for patients and clinicians. The prevalence of hypertrophic scarring can be up to 70% after burns, and patients suffer from pain, itching, and loss of joint mobility. To date, the exact mechanisms underlying hypertrophic scar formation are unclear, and clinical options remain limited. Recent Advances: Several studies have demonstrated that pathological scars are a type of hyperactive vascular response to wounding. Scar regression has been found to be accompanied by microvessel occlusion, which causes severe hypoxia, malnutrition, and endothelial dysfunction, suggesting the essential roles of microvessels in scar regression. Therefore, interventions that target the vasculature, such as intense pulsed light, pulsed dye lasers, vascular endothelial growth factor antibodies, and Endostar, represent potential treatments. In addition, the mass of scar-associated collagen is usually not considered by current treatments. However, collagen-targeted therapies such as fractional CO₂ laser and collagenase have shown promising outcomes in scar treatment. Critical Issues: Traditional modalities used in current clinical practice only partially target scar-associated microvessels or collagen. As a result, the effectiveness of current treatments is limited and is too often accompanied by undesirable side effects. The formation of scars in the early stage is mainly affected by microvessels, whereas the scars in later stages are mostly composed of residual collagen. Traditional therapies do not utilize specific targets for scars at different stages. Therefore, more precise treatment strategies are needed. Future Directions: Scars should be classified as either "vascular-dominant" or "collagen-dominant" before selecting a treatment. In this way, strategies that are vascular-targeted, collagen-targeted, or a combination thereof could be recommended to treat scars at different stages.

Orchestrating the Dermal/Epidermal Tissue Ratio during Wound Healing by Controlling the Moisture Content

A balanced and moist wound environment and surface increases the effect of various growth factors, cytokines, and chemokines, stimulating cell growth and wound healing. Considering this fact, we tested in vitro and in vivo water evaporation rates from the cellulose dressing epicite^hydro when combined with different secondary dressings as well as the resulting wound healing efficacy in a porcine donor site model. The aim of this study was to evaluate how the different rates of water evaporation affected wound healing efficacy. To this end, epicite^hydro primary dressing, in combination with different secondary dressing materials (cotton gauze, JELONET^◊, AQUACEL^® Extra ™, and OPSITE^◊ Flexifix), was placed on 3 × 3 cm-sized dermatome wounds with a depth of 1.2 mm on the flanks of domestic pigs. The healing process was analyzed histologically and quantified by morphometry. High water evaporation rates by using the correct secondary dressing, such as cotton gauze, favored a better re-epithelialization in comparison with the low water evaporation resulting from an occlusive secondary dressing, which favored the formation of a new and intact dermal tissue that nearly fully replaced all the dermis that was removed during wounding. This newly available evidence may be of great benefit to clinical wound management.

TGF-β loaded exosome enhances ischemic wound healing in vitro and in vivo

Rationale: With over seven million infections and $25 billion treatment cost, chronic ischemic wounds are one of the most serious complications in the United States. The controlled release of bioactive factor enriched exosome from finbrin gel was a promising strategy to promote wound healing. Methods: To address this unsolved problem, we developed clinical-grade platelets exosome product (PEP), which was incorporate with injectable surgical fibrin sealant (TISSEEL), to promote chronic wound healing and complete skin regeneration. The PEP characterization stimulated cellular activities and in vivo rabbit ischemic wound healing capacity of TISSEEL-PEP were performed and analyzed. Results: PEP, enriched with transforming growth factor beta (TGF-β), possessed exosomal characteristics including exosome size, morphology, and typical markers including CD63, CD9, and ALG-2-interacting protein X (Alix). In vitro, PEP significantly promoted cell proliferation, migration, tube formation, as well as skin organoid formation. Topical treatment of ischemic wounds with TISSEEL-PEP promoted full-thickness healing with the reacquisition of hair follicles and sebaceous glands. Superior to untreated and TISSEEL-only treated controls, TISSEEL-PEP drove cutaneous healing associated with collagen synthesis and restoration of dermal architecture. Furthermore, PEP promoted epithelial and vascular cell activity enhancing angiogenesis to restore blood flow and mature skin function. Transcriptome deconvolution of TISSEEL-PEP versus TISSEEL-only treated wounds prioritized regenerative pathways encompassing neovascularization, matrix remodeling and tissue growth. Conclusion: This room-temperature stable, lyophilized exosome product is thus capable of delivering a bioactive transforming growth factor beta to drive regenerative events.

A six-herb Chinese medicine composition ointment as a promising candidate for treatment of hypertrophic scars

Objective

To study the anti-hypertrophic scar effect of the six-herb Chinese medicine composition (SCMC) ointment on the rabbit ear hypertrophic scar models.

Methods

The optimal formulation of SCMC ointment matrix was screened by the orthogonal designs and a series of evaluation tests. The SCMC ointment was prepared through emulsifying method. The rabbit ear hypertrophic scar models were established and used to investigate the anti-hypertrophic scar effect of SCMC ointment.

Results

Our results demonstrated that all the quality control indications of the SCMC ointment met the requirements. Anti-hypertrophic scar activity results showed that all the rabbit ear scar tissues appeared different degrees of shrink and fading, and took an unobvious but palpable shift from hard to soft texture with the low, middle and high concentration SCMC ointments treatments in vivo. Additionally, on 21st day the scar area and thickness in different concentrations of SCMC ointment groups were significantly reduced than control group, in a concentration-dependent manner. The immunohistochemical results also indicated that the SCMC ointment had good anti-hypertrophic scar properties and could inhibit hypertrophic scar formation.

Conclusion

The SCMC ointment could improve the blood circulation condition of hypertrophic scar tissues. Our research has demonstrated the Chinese medicine composition ointment with good anti-hypertrophic scar properties that could be used to treat hypertrophic scars. Meanwhile, it provides a theoretical basis for further clinical application.

Assessment of Transdermal Delivery of Topical Compounds in Skin Scarring Using a Novel Combined Approach of Raman Spectroscopy and High-Performance Liquid Chromatography

Objective: The goal of any topical formulation is efficient transdermal delivery of its active components. However, delivery of compounds can be problematic with penetration through tough layers of fibrotic dermal scar tissue. Approach: We propose a new approach combining high-performance liquid chromatography (HPLC) and Raman spectroscopy (RS) using a topical of unknown composition against a well-known antiscar topical (as control). Results: Positive detection of compounds within the treatment topical using both techniques was validated with mass spectrometry. RS detected conformational structural changes; the 1,655/1,446 cm^-1 ratio estimating collagen content significantly decreased (p < 0.05) over weeks 4, 12, and 16 compared with day 0. The amide I band, known to represent collagen and protein in skin, shifted from 1,667 to 1,656 cm^-1, which may represent a change from β-sheets in elastin to α-helices in collagen. Confirmatory elastin immunohistochemistry decreased compared with day 0, conversely the collagen I/III ratio increased in the same samples by week 12 (p < 0.05, and p < 0.0001, respectively), in keeping with normal scar formation. Optical coherence tomography attenuation coefficient representing collagen deposition was significantly decreased at week 4 compared with day 0 and increased at week 16 (p < 0.05). Innovation: This study provides a platform for further research on the simultaneous evaluation of the effects of compounds in cutaneous scarring by RS and HPLC, and identifies a role for RS in the therapeutic evaluation and theranostic management of skin scarring. Conclusions: RS can provide noninvasive information on the effects of topicals on scar pathogenesis and structural composition, validated by other analytical techniques.

Reduced hydration-induced decreased caveolin-1 expression causes epithelial-to-mesenchymal transition

The reduced hydration environment induced by disruption of epithelial barrier function after injury results in excessive scarring, but the underlying mechanisms are poorly understood. We demonstrated that exposing keratinocytes to a reduced hydration environment causes epithelial-to-mesenchymal transition (EMT) and induces caveolin-1-dependent downregulation of E-cadherin. Reduced caveolin-1 expression and increased Snail expression are associated with low expression levels of E-cadherin. Caveolin-1 downregulation increases the transcriptional activity of β-catenin-TCF/LEF-1, and overexpression of caveolin-1 inhibits EMT that results from reduced hydration. Our findings suggest a role for caveolin-1 downregulation in linking aberrant EMT to the reduced hydration environment: findings that may lead to new developments in the prevention and treatment of hypertrophic scar.

Evolution of ischemia and neovascularization in a murine model of full thickness human wound healing

Translation of wound healing research is limited by the lack of an appropriate animal model, due to the anatomic and wound healing differences in animals and humans. Here, we characterize healing of grafted, full-thickness human skin in an in vivo model of wound healing. Full-thickness human skin, obtained from reconstructive operations, was grafted onto the dorsal flank of NOD.Cg-KitW41J Tyr + Prkdcscid Il2rgtm1Wjl /ThomJ mice. The xenografts were harvested 1 to 12 weeks after grafting, and histologic analyses were completed for viability, neovascularization, and hypoxia. Visual inspection of the xenograft shows drying and sloughing of the epidermis starting at week four. By week 12, the xenograft appears healed but has lost 63.05 ± 0.24% of the initial graft size. There is histologic evidence of epidermolysis as early as 2 weeks, which progresses until week 4, when new epidermis appears from the wound edges. Epidermal regeneration is complete by week 12, although the epidermis appears hypertrophied. An initial increase of infiltrating immune mouse cells into the xenograft normalizes to baseline 6 months after grafting. Neovascularization, as evidenced by positive staining for the proteins human CD31 and alpha smooth muscle actin, is present as early as 2 weeks after grafting at the interface between the xenograft and the mouse tissue. CD31 and alpha smooth muscle actin staining increased throughout the xenograft over the 12 weeks, leading to greater viability of the tissue. Likewise, there is increased Hypoxia Inducible Factor 1-alpha expression at the interface of viable and nonviable tissue, which suggest a hypoxia-driven process causing early graft loss. These findings illustrate human skin wound healing in an ischemic environment, providing a timeline for use of full thickness human skin after grafting in a murine model to study mechanisms underlying human skin wound healing.

Inflammation as an orchestrator of cutaneous scar formation: a review of the literature

Inflammation is a key phase in the cutaneous wound repair process. The activation of inflammatory cells is critical for preventing infection in contaminated wounds and results in the release of an array of mediators, some of which stimulate the activity of keratinocytes, endothelial cells, and fibroblasts to aid in the repair process. However, there is an abundance of data suggesting that the strength of the inflammatory response early in the healing process correlates directly with the amount of scar tissue that will eventually form. This review will summarize the literature related to inflammation and cutaneous scar formation, highlight recent discoveries, and discuss potential treatment modalities that target inflammation to minimize scarring.

Strategies to prevent hypertrophic scar formation: a review of therapeutic interventions based on molecular evidence

Once scar tissues mature, it is impossible for the surrounding tissue to regenerate normal dermal tissue. Therefore, it is essential to understand the fundamental mechanisms and establish effective strategies to inhibit aberrant scar formation. Hypertrophic scar formation is considered a result of the imbalance between extracellular matrix synthesis and degradation during wound healing. However, the underlying mechanisms of hypertrophic scar development are poorly understood. The purpose of this review was to outline the management in the early stage after wound healing to prevent hypertrophic scar formation, focusing on strategies excluding therapeutic agents of internal use. Treatment aimed at molecular targets, including cytokines, will be future options to prevent and treat hypertrophic scars. More basic studies and clinical trials, including combination therapy, are required to investigate the mechanisms and prevent hypertrophic scar formation.

Diagnosis and Treatment of Keloids and Hypertrophic Scars-Japan Scar Workshop Consensus Document 2018

There has been a long-standing need for guidelines on the diagnosis and treatment of keloids and hypertrophic scars that are based on an understanding of the pathomechanisms that underlie these skin fibrotic diseases. This is particularly true for clinicians who deal with Asian and African patients because these ethnicities are highly prone to these diseases. By contrast, Caucasians are less likely to develop keloids and hypertrophic scars, and if they do, the scars tend not to be severe. This ethnic disparity also means that countries vary in terms of their differential diagnostic algorithms. The lack of clear treatment guidelines also means that primary care physicians are currently applying a hotchpotch of treatments, with uneven outcomes. To overcome these issues, the Japan Scar Workshop (JSW) has created a tool that allows clinicians to objectively diagnose and distinguish between keloids, hypertrophic scars, and mature scars. This tool is called the JSW Scar Scale (JSS) and it involves scoring the risk factors of the individual patients and the affected areas. The tool is simple and easy to use. As a result, even physicians who are not accustomed to keloids and hypertrophic scars can easily diagnose them and judge their severity. The JSW has also established a committee that, in cooperation with outside experts in various fields, has prepared a Consensus Document on keloid and hypertrophic scar treatment guidelines. These guidelines are simple and will allow even inexperienced clinicians to choose the most appropriate treatment strategy. The Consensus Document is provided in this article. It describes (1) the diagnostic algorithm for pathological scars and how to differentiate them from clinically similar benign and malignant tumors, (2) the general treatment algorithms for keloids and hypertrophic scars at different medical facilities, (3) the rationale behind each treatment for keloids and hypertrophic scars, and (4) the body site-specific treatment protocols for these scars. We believe that this Consensus Document will be helpful for physicians from all over the world who treat keloids and hypertrophic scars.

In vivo terahertz imaging to evaluate scar treatment strategies: silicone gel sheeting

Silicone gel sheeting (SGS) is widely used for scar treatment; however, studies showing its interaction with skin and efficacy of scar treatment are still lacking. THz light is non-ionizing and highly sensitive to changes in water content and thus skin hydration. In this work, we use in-vivo THz imaging to monitor how SGS affects the THz response of human skin during occlusion, and the associated THz reflectivity and refractive index changes are presented. We find that SGS effectively hydrates the skin beneath it, with minimal lateral effects beyond the sheeting. Our work demonstrates that THz imaging is able to detect the subtle hydration changes on the surface of human skin caused by SGS, and it has the potential to be used to evaluate different scar treatment strategies.

Conservative treatment of fingertip injuries in children - first experiences with a novel silicone finger cap that enables woundfluid analysis

Introduction: Human fingertips are able to regenerate soft tissue and skin after amputation injuries with excellent cosmetic and functional results when treated with semiocclusive dressings. Despite bacterial colonizations, proceeding infections are not reported with this management. The underlying mechanisms for this form of regenerative healing as well as for the resilience to infections are not known. Due to the lack of mechanical protection, the leakage of maloderous woundfluid and the sometimes challenging application, conventional film dressings have their problems, especially in treating young children. We therefore treated selected patients with a novel silicone finger cap with an integrated wound fluid reservoir that enables atraumatic routine wound fluid aspiration.

Methods: We report on 34 patients in between 1 and 13 years with traumatic fingertip amputations primarily treated with occlusive dressings. 12 patients were treated with a novel silicone finger cap. We summarized clinical data for each patient. This included photographs and microbiological results from wound fluid analyses, whenever available.

Results: The results of both, conventional film dressing and silicone finger cap treatment, were excellent with no hypersensitivity and no restrictions in sensibility and motility. Even larger pulp defects were rearranged in a round shape and good soft tissue coverage of the distal phalanx was achieved. Nail deformities were not observed. We detected a wide spectrum of both aerobic and anaerobic bacteria in the wound fluids but infections were not observed. Epithelialization times did not differ significantly and no severe complications were seen in all primarily conservatively treated patients.

Conclusion: This study provides preliminary data demonstrating that the treatment with the silicone finger cap leads to excellent clinical results in wound healing. Interestingly, the wounds were colonized with a wide range of bacteria including species that may cause wound infections. However, we saw no proceeding inflammation and the regeneration was undisturbed. In the future, the efficacy of this new management should be evaluated in randomized, controlled clinical trials to confirm the results under standard conditions and get more insight into the role of the wound microbiome as well as other factors that may promote regeneration. The aspirable Reservoir of the finger cap will enable easy atraumatic sampling of wound fluids both for diagnostic and for research purposes as well as possibly allowing direct administration of pro-regenerative drugs in the future.

Epidermal HMGB1 Activates Dermal Fibroblasts and Causes Hypertrophic Scar Formation in Reduced Hydration

HMGB1 protein is a multifunctional cytokine involved in inflammatory reactions and is known to play a key role in tissue repair and fibrosis. However, the function of HMGB1 in fibrotic skin diseases, such as hypertrophic scar formation, remains unclear. In this study, HMGB1 was detected in the nuclei of epidermal cells in normal skin and had accumulated in the cytoplasm in hypertrophic scars. By establishing a keratinocyte-fibroblast co-culture and conditional medium treatment models, we found that a reduced hydration condition increased the expression and secretion of HMGB1 in keratinocytes, subsequently activating dermal fibroblasts. HMGB1 secreted from keratinocytes activated fibroblasts by promoting the nuclear import of MRTF-A, increased the nuclear accumulation of MRTF-A/SRF complexes and consequently enhanced α-smooth muscle actin promoter activation. Moreover, blockade of advanced glycation end products or Toll-like receptor 2/4 inhibited the fibroblast activation induced by HMGB1. Finally, local delivery of HMGB1 resulted in marked hypertrophic scar formation in rabbit hypertrophic scar models, while HMGB1 blockade exerted a clear anti-scarring effect. Our results indicate that high HMGB1 levels induced by a reduced hydration status play an important role in hypertrophic scar formation, strongly suggesting that HMGB1 is a novel target for preventing scarring.

Endothelial cells enhance adipose mesenchymal stromal cell-mediated matrix contraction via ALK receptors and reduced follistatin: Potential role of endothelial cells in skin fibrosis

Abnormal cutaneous wound healing can lead to formation of fibrotic hypertrophic scars. Although several clinical risk factors have been described, the cross‐talk between different cell types resulting in hypertrophic scar formation is still poorly understood. The aim of this in vitro study was to investigate whether endothelial cells (EC) may play a role in skin fibrosis, for example, hypertrophic scar formation after full‐thickness skin trauma. Using a collagen/elastin matrix, we developed an in vitro fibrosis model to study the interaction between EC and dermal fibroblasts or adipose tissue‐derived mesenchymal stromal cells (ASC). Tissue equivalents containing dermal fibroblasts and EC displayed a normal phenotype. In contrast, tissue equivalents containing ASC and EC displayed a fibrotic phenotype indicated by contraction of the matrix, higher gene expression of ACTA2, COL1A, COL3A, and less secretion of follistatin. The contraction was in part mediated via the TGF‐β pathway, as both inhibition of the ALK4/5/7 receptors and the addition of recombinant follistatin resulted in decreased matrix contraction (75 ± 11% and 24 ± 8%, respectively). In conclusion, our study shows that EC may play a critical role in fibrotic events, as seen in hypertrophic scars, by stimulating ASC‐mediated matrix contraction via regulation of fibrosis‐related proteins.

The molecular pathogenesis of morphoea: from genetics to future treatment targets

A number of immunoinflammatory and profibrotic mechanisms are recognized in the pathogenesis of broad sclerotic skin processes and, more specifically, morphoea. However, the precise aetiopathogenesis is complex and remains unclear. Morphoea is clinically heterogeneous, with variable anatomical patterning, depth of tissue involvement and sclerotic, inflammatory, atrophic and dyspigmented morphology. Underlying mechanisms determining these reproducible clinical subsets are poorly understood but of great clinical and therapeutic relevance. Regional susceptibility mechanisms (e.g. environmental triggers, mosaicism and positional identity) together with distinct pathogenic determinants (including innate, adaptive and imbalanced pro- and antifibrotic signalling pathways) are likely implicated. In the age of genetic profiling and personalized medicine, improved characterization of the environmental, systemic, local, genetic and immunopathological factors underpinning morphoea pathogenesis may open the door to novel targeted therapeutic approaches.

Wound bed preparation: A novel approach using HydroTherapy

Wounds that fail to heal quickly are often encountered by community nursing staff. An important step in assisting these chronic or stalled wounds progress through healing is debridement to remove devitalised tissue, including slough and eschar, that can prevent the wound from healing. A unique wound treatment called HydroTherapy aims to provide an optimal healing environment. The first step of HydroTherapy involves HydroClean plus™, this dressing enables removal of devitalised tissue through autolytic debridement and absorption of wound fluid. Irrigation and cleansing provided by Ringer's solution from the dressing further removes any necrotic tissue or eschar. Once effective wound bed preparation has been achieved a second dressing, HydroTac™, provides an ongoing hydrated wound environment that enables re-epithelialisation to occur in an unrestricted fashion. This paper presents 3 case studies of slow healing wounds treated with HydroClean plus™ which demonstrates effective wound debridement.

The immediate use of a silicone sheet wound closure device in scar reduction and prevention

Silicone has been used successfully postoperatively in the prevention of hypertrophic and other types of adverse scars. The Silicone Suture Plate (SSP) is a new, minimally invasive, sterile wound closure device that is applied intraoperatively to prevent adverse scarring. The SSP device permits immediate application of silicone while concurrently allowing for wound-edge tension redistribution. In this prospective, controlled, single-blinded clinical study, 8 consecutive patients undergoing deep-plane rhytidectomy were selected. SSP devices were placed on the patients' posterior rhytidectomy hairline incision; the mirror-image control site underwent standard suturing techniques. Three blinded, independent raters assessed the treatment and control sides at 6-week and 4-month follow-up visits, using the Objective Scar Assessment Scale (OSAS), a validated scar assessment tool. The 6-week OSAS scores revealed an 18.4% improvement on the side with the SSP device (13.3) when compared to the control side (16.3). The 4-month OSAS scores showed a 27.3% improvement on the treatment side from 12.7 (control) to 9.2 (SSP). These OSAS results were found to be statistically significant when taken as an aggregate of the observers' scores, but not when observers' scores were measured individually (p < 0.05). In our series of patients, we showed promising results with the use of the SSP device. Early silicone application and tissue tension distribution contributed to an overall more aesthetically pleasing scar compared to those seen with standard suturing techniques, although more testing is required.

Pharmacological Evaluation of Chrozophora tinctoria as Wound Healing Potential in Diabetic Rat's Model

Objective. The study was designed to evaluate pharmacological potential of hydroalcoholic leaves extract of Chrozophora tinctoria intended for wound healing in diabetic rats' model. Methods. The method used to evaluate the pharmacological potential of hydroalcoholic leave extract was physical incision rat model. In this model, cutting of the skin and/or other tissues with a sharp blade has been made and the rapid disruption of tissue integrity with minimal collateral damage was observed shortly. Animals used in the study were divided into four groups that consist of six animals in each group. Group I serves as normal control, Group II serves as disease control, Group III was used as standard treatment (Povidone iodine 50 mg/kg b.w.), and Group IV was used for test drug (C. tinctoria 50 mg/kg b.w.). Result. The hydroalcoholic leave extract of Chrozophora tinctoria has been significantly observed to heal the wound (98%) in diabetic rats within 21 days, while standard drug (Povidone iodine) healed the wound about 95% in the same condition. The oral dose (50 mg/kg b.w.) of Chrozophora tinctoria was also found to improve the elevated blood glucose level in comparison to disease control group, which increased after the oral administration of Streptozotocin. Conclusion. The Chrozophora tinctoria has significant wound healing potential in the animal having physically damaged tissue in diabetic condition.

Efficacy and Safety of a Novel 100% Silicone Scar Gel Treatment for Early Intervention in Scar Management

Objective: To evaluate the efficacy and safety of a new topical silicone gel for the early intervention in the management of scars. Design: In this 12-week, observational study, healthy subjects (n=15) with an accessible linear or hypertrophic scar were given the test product and instructed to apply twice daily. Subjects returned 14, 28, 56, and 84 days later for evaluation and recording of adverse events. Setting: Private practice of the author. Participants: Eligible subjects had a scar with a Vancouver Scar Scale total score ≥3 at baseline. Measurements: Improvement was evaluated by the Vancouver Scar Scale and Observer Scar Assessment Scale at baseline and at four follow-up visits. Results: The median total Vancouver Scar Scale score and median total Observer Scar Assessment Scale score decreased significantly from baseline at each visit, showing rapid and continuing improvement in the appearance of the scars. For Vancouver Scar Scale, significant differences of individual parameters from baseline began at 28 days for pliability and height, 56 days for vascularity, and 84 days for pigmentation. For Observer Scar Assessment Scale parameters, significant differences from baseline began at 14 days and continued until 84 days for vascularization, thickness, and pigmentation. Pain and pruritis scores were low at each visit. Overall, 84.6 percent of subjects rated the treatment as excellent, very good, or good after three months of treatment. No adverse events were reported. Conclusion: The test product improved the appearance of scars after three months of twice-daily treatment and without adverse events.

Physical and Mechanical Evaluation of Silicone-Based Double-Layer Adhesive Patch Intended for Keloids and Scar Treatment Therapy

Growing interest in silicone elastomers for pharmaceutical purposes is due to both their beneficial material effect for scar treatment and their potential as drug carriers. Regarding their morphological structure, silicone polymers possess unique properties, which enable a wide range of applicability possibilities. The present study focused on developing a double-layer adhesive silicone film (DLASil) by evaluating its physical and mechanical properties, morphology, and stability. DLASil suitability for treatment of scars and keloids was evaluated by measurement of tensile strength, elasticity modulus, and elongation. The results indicated that mechanical and physical properties of the developed product were satisfying.

S100A12 Induced in the Epidermis by Reduced Hydration Activates Dermal Fibroblasts and Causes Dermal Fibrosis

Disruption of the barrier function of skin increases transepidermal water loss and up-regulates inflammatory pathways in the epidermis. Consequently, sustained expression of proinflammatory cytokines from the epidermis is associated with dermal scarring. We found increased expression of S100A12 in the epidermis of human hypertrophic and keloid scar. Exposing a stratified keratinocyte culture to a reduced-hydration environment increased the expression and secretion of S100A12 by nearly 70%, which in turn activated dermal fibroblasts in vitro. Direct treatment of fibroblasts with conditioned medium collected from stratified keratinocyte culture under reduced-hydration conditions activated fibroblasts, shown by up-regulation of α-smooth muscle actin, pro-collagen 1, and F-actin expression. However, this fibroblast activation was not found when S100A12 was knocked down by RNA interference in keratinocytes. Pharmacological blockade of S100A12 receptors, RAGE, or TLR4 inhibited S100A12-induced fibroblast activation. Local delivery of S100A12 resulted in a marked hypertrophic scar formation in a validated rabbit hypertrophic scar model compared with saline control. Our findings indicate that S100A12 functions as a proinflammatory cytokine and suggest that S100A12 is a potential therapeutic target for dermal scarring.

Cutaneous Imaging Technologies in Acute Burn and Chronic Wound Care

BACKGROUND

Wound assessment relies on visual evaluation by physicians. Such assessment is largely subjective and presents the opportunity to explore the use of emergent technologies.

METHODS

Emergent and powerful noninvasive imaging technologies applicable to assess burn and chronic wounds are reviewed.

RESULTS

The need to estimate wound depth is critical in both chronic wound and burn injury settings. Harmonic ultrasound technology is powerful to study wound depth. It addresses the limitations of optical imaging with limited depth of penetration. What if a wound appears epithelialized by visual inspection, which shows no discharge yet is covered by repaired skin that lacks barrier function? In this case although the wound is closed as defined by current standards, it remains functionally open, presenting the risk of infection and other postclosure complications. Thus, assessment of skin barrier function is valuable in the context of assessing wound closure. Options for the study of tissue vascularization are many. If noncontact and noninvasive criteria are of importance, laser speckle imaging is powerful. Fluorescence imaging is standard in several clinical settings and is likely to serve the wound clinics well as long as indocyanine green injection is not of concern. A major advantage of harmonic ultrasound imaging of wound depth is that the same system is capable of providing information on blood flow dynamics in arterial perforators.

CONCLUSION

With many productive imaging platforms to choose from, wound care is about to be transformed by technology that would help assess wound severity.

Partial epithelial-mesenchymal transition in keloid scars: regulation of keloid keratinocyte gene expression by transforming growth factor-β1

Background

Keloids are an extreme form of abnormal scarring that result from a pathological fibroproliferative wound healing process. The molecular mechanisms driving keloid pathology remain incompletely understood, hindering development of targeted, effective therapies. Recent studies in our laboratory demonstrated that keloid keratinocytes exhibit adhesion abnormalities and display a transcriptional signature reminiscent of cells undergoing epithelial-mesenchymal transition (EMT), suggesting a role for EMT in keloid pathology. In the current study, we further define the EMT-like phenotype of keloid scars and investigate regulation of EMT-related genes in keloid.

Methods

Primary keratinocytes from keloid scar and normal skin were cultured in the presence or absence of transforming growth factor beta 1 (TGF-β1) +/− inhibitors of TGF-β1 and downstream signaling pathways. Gene expression was measured using quantitative polymerase chain reaction. Migration was analyzed using an in vitro wound healing assay. Proteins in keloid scar and normal skin sections were localized by immunohistochemistry. Statistical analyses utilized SigmaPlot (SyStat Software, San Jose, CA) or SAS^® (SAS Institute, Cary, NC).

Results

In keloid and normal keratinocytes, TGF-β1 regulated expression of EMT-related genes, including hyaluronan synthase 2, vimentin, cadherin-11, wingless-type MMTV integration site family, member 5A, frizzled 7, ADAM metallopeptidase domain 19, and interleukin-6. Inhibition of canonical TGF-β1 signaling in keloid keratinocytes significantly inhibited expression of these genes, and TGF-β1 stimulation of normal keratinocytes increased their expression. The inhibition of the extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway or the p38 mitogen-activated protein kinase pathway attenuated TGF-β1-induced expression of subsets of these genes. Migration of keloid keratinocytes, previously shown to be increased compared with normal keratinocytes, was significantly reduced by inhibition of TGF-β1 or ERK1/2 signaling. Biomarkers of EMT, including reduced E-cadherin and increased active β-catenin, were observed in keloid epidermis in vivo. However, evidence of basement membrane breakdown in keloid scar was not observed.

Conclusions

The results suggest that keloid keratinocytes exist in an EMT-like metastable state, similar to activated keratinocytes in healing wounds. The EMT-like gene expression pattern of keloid keratinocytes is regulated by canonical and non-canonical TGF-β1 signaling pathways. Therefore, interventions targeting TGF-β1-regulated EMT-like gene expression in keloid keratinocytes may serve to suppress keloid scarring.

Electronic supplementary material

The online version of this article (doi:10.1186/s41038-016-0055-7) contains supplementary material, which is available to authorized users.

The importance of hydration in wound healing: reinvigorating the clinical perspective

Balancing skin hydration levels is important as any disruption in skin integrity will result in disturbance of the dermal water balance. The discovery that a moist environment actively supports the healing response when compared with a dry environment highlights the importance of water and good hydration levels for optimal healing. The benefits of 'wet' or 'hyper-hydrated' wound healing appear similar to those offered by moist over a dry environment. This suggests that the presence of free water may not be detrimental to healing, but any adverse effects of wound fluid on tissues is more likely related to the biological components contained within chronic wound exudate, for example elevated protease levels. Appropriate dressings applied to wounds must not only be able to absorb the exudate, but also retain this excess fluid together with its protease solutes, while concurrently preventing desiccation. This is particularly important in the case of chronic wounds where peri-wound skin barrier properties are compromised and there is increased permeation across the injured skin. This review discusses the importance of appropriate levels of hydration in skin, with a particular focus on the need for optimal hydration levels for effective healing. Declaration of interest: This paper was supported by Paul Hartmann Ltd. The authors have provided consultative services to Paul Hartmann Ltd.

Angiogenesis and wound repair: when enough is enough

All animals heal, and the ability to heal is requisite for human health. One aspect of repair that has always been considered to be essential for adequate healing is the creation of a new vasculature via angiogenesis. As adult skin wounds heal, a period of rapid and robust capillary growth creates a vascular bed that has many fold more capillaries than does normal tissue. Over time, most of the newly formed capillaries regress, resulting in a final vascular density similar to that of normal skin. Certainly, new capillaries are necessary to bring nutrients, immune cells, and oxygen to healing wounds. Yet, the presumed functional importance of an overabundance of capillaries has recently been challenged, creating questions about whether excess capillary growth is truly necessary for healing. In particular, studies of wounds that heal exceptionally quickly and with less scar formation, such as those in fetal skin and oral mucosa, show that these tissues heal with a reduced angiogenic burst composed of more mature vessels that provide better oxygenation. The level of angiogenesis in wounds often correlates with the inflammatory response, largely because inflammatory cells produce an abundance of proangiogenic mediators. Both the selective reduction of inflammation and the selective reduction of angiogenesis have now been suggested as ways to improve scarring. These concepts link excessive inflammation and the production of a dense but poorly perfused capillary bed to inferior healing outcomes.

Integrin-mediated regulation of epidermal wound functions

During cutaneous wound healing, keratinocyte proliferation and migration are critical for re-epithelialization. In addition the epidermis secretes growth factors, cytokines, proteases, and matricellular proteins into the wound microenvironment that modify the extracellular matrix and stimulate other wound cells that control the inflammatory response, promote angiogenesis and facilitate tissue contraction and remodeling. Wound keratinocytes express at least seven different integrins-the major cell adhesion receptors for the extracellular matrix-that collectively control essential cell-autonomous functions to ensure proper re-epithelialization, including migration, proliferation, survival and basement membrane assembly. Moreover, it has become evident in recent years that some integrins can regulate paracrine signals from wound epidermis that stimulate other wound cells involved in angiogenesis, contraction and inflammation. Importantly, it is likely that abnormal integrin expression or function in the epidermis contributes to wound pathologies such as over-exuberant healing (e.g., hypertrophic scar formation) or diminished healing (e.g., chronic wounds). In this review, we discuss current knowledge of integrin function in the epidermis, which implicates them as attractive therapeutic targets to promote wound healing or treat wound pathologies. We also discuss challenges that arise from the complex roles that multiple integrins play in wound epidermis, which may be regulated through extracellular matrix remodeling that determines ligand availability. Indeed, understanding how different integrin functions are temporally coordinated in wound epidermis and which integrin functions go awry in pathological wounds, will be important to determine how best to target them clinically to achieve maximum therapeutic benefit. Graphical abstract In addition to their well-characterized roles in keratinocyte adhesion, migration and wound re-epithelialization, epidermal integrins play important roles in modifying the wound microenvironment by regulating the expression and secretion of growth factors, extracellular proteases, and matricellular proteins that stimulate other wound cells, including vascular endothelial cells and fibroblasts/myofibroblasts.

Currently known risk factors for hypertrophic skin scarring: A review

OBJECTIVE

The study aims to provide an overview of risk factors for hypertrophic scarring.

BACKGROUND

Hypertrophic skin scarring remains a major concern in medicine and causes considerable morbidity. Despite extensive research on this topic, the precise mechanism of excessive scarring is still unknown. In addition, the current literature lacks an overview of the possible risk factors in the development of hypertrophic scars.

METHODS

PubMed searches were performed on risk factors for hypertrophic scar (HTS) formation.

RESULTS

Eleven studies suggesting nine factors associated with HTS formation were found. Studies concerning chemotherapy, age, stretch, infection, and smoking have a moderate to high strength of evidence, but some other factors have not been studied in a convincing manner or are still disputed.

CONCLUSIONS

Risk factors for HTS formation are young age, bacterial colonization, and skin subjected to stretch. Chemotherapy, statins, and smoking seem to play a protective role in HTS formation.

A comprehensive evidence-based review on the role of topicals and dressings in the management of skin scarring

Wound healing after dermal injury is an imperfect process, inevitably leading to scar formation as the skin re-establishes its integrity. The resulting scars have different characteristics to normal skin, ranging from fine-line asymptomatic scars to problematic scarring including hypertrophic and keloid scars. Scars appear as a different colour to the surrounding skin and can be flat, stretched, depressed or raised, manifesting a range of symptoms including inflammation, erythema, dryness and pruritus, which can result in significant psychosocial impact on patients and their quality of life. In this paper, a comprehensive literature review coupled with an analysis of levels of evidence (LOE) for each published treatment type was conducted. Topical treatments identified include imiquimod, mitomycin C and plant extracts such as onion extract, green tea, Aloe vera, vitamin E and D, applied to healing wounds, mature scar tissue or fibrotic scars following revision surgery, or in combination with other more established treatments such as steroid injections and silicone. In total, 39 articles were included, involving 1703 patients. There was limited clinical evidence to support their efficacy; the majority of articles (n = 23) were ranked as category 4 LOE, being of limited quality with individual flaws, including low patient numbers, poor randomisation, blinding, and short follow-up periods. As trials were performed in different settings, they were difficult to compare. In conclusion, there is an unmet clinical need for effective solutions to skin scarring, more robust long-term randomised trials and a consensus on a standardised treatment regime to address all aspects of scarring.

Anti-aging and filling efficacy of six types hyaluronic acid based dermo-cosmetic treatment: double blind, randomized clinical trial of efficacy and safety

Background

Human skin aging is a multifactorial and complex biological process affecting the different skin constituents. Even if the skin aging mechanism is not yet fully unravelled is evident that epidermis loses the principal molecule responsible for binding and retaining water molecules, resulting in loss of skin moisture and accounting for some of the most striking alterations of the aged skin.

Objectives

This Study investigated the cosmetic filling efficacy of Fillerina® in decreasing the skin aging signs and in improving facial volume deficiencies.

Methods

A placebo-controlled, double-blind, randomized clinical trial was carried out on 40 healthy female subjects showing mild to moderate clinical signs of skin aging. The effect of the treatment on skin surface and on face volumes was assessed both in the short-term (3 h after a single product application) and in the long-term (7, 14, and 30 days after continuative daily use).

Results

Three hours after a single application and after 7, 14, and 30 days of treatment the lips volume was increased by 8.5%, 11.3%, 12.8%, and 14.2%. After 7, 14, and 30 days: (1) skin sagging of the face contours was decreased by −0.443 ± 0.286, −1.124 ± 0.511, and −1.326 ± 0.649 mm, respectively; (2) skin sagging of the cheekbones contours was decreased by −0.989 ± 0.585, −2.500 ± 0.929, and −2.517 ± 0.927 mm, respectively; (3) cheekbones volume was increased by 0.875 ± 0.519, 2.186 ± 0.781, and 2.275 ± 0.725 mm, respectively; (4) wrinkle volume was decreased by −11.3%, −18.4%, and −26.3%, respectively; and (5) wrinkle depth was decreased by −8.4%, −14.5%, and −21.8% respectively.

Conclusion

This study demonstrated the positive filling effect of Fillerina® in decreasing the clinical signs of skin aging and in improving the face volumes.

Morphological effects of mitomycin C on urothelial responses to experimentally-induced urethral stricture in rats

OBJECTIVES

To analyze the urothelial responses to mitomycin C treatment after urethral injury in rats, as the urothelium might play a role in the pathogenesis of urethral stricture.

METHODS

Male Sprague-Dawley rats were divided into four groups (n = 5/group): negative control, positive control without further treatment, experimental control treated with sodium hyaluronate and sodium carboxymethylcellulose, and experimental treated with mitomycin C after internal urethrotomy.

RESULTS

Compared with negative controls, positive controls showed a significant increase in cell proliferation and DNA damage accompanied by a considerable decrease in DNA repair in the urothelium, which resulted in urethral stricture. Experimental controls showed a significant increase in cell proliferation, DNA damage and DNA repair compared with negative controls. The mitomycin C-treated group showed a significant decrease in cell proliferation and DNA damage, but a considerable increase in DNA repair compared with the positive and experimental control groups. DNA damage was immediately increased after urethral injury, but DNA repair and cell proliferation showed belated and upregulated expression after mitomycin C treatment.

CONCLUSIONS

Mitomycin C could induce healthy re-epithelialization without severe damage in the urothelium. This finding might support the possibility of using mitomycin C as an adjuvant therapy for urethral strictures, and it might also suggest a urothelial role in the process of urethral stricture after urethral injury.

Abnormally differentiating keratinocytes in the epidermis of systemic sclerosis patients show enhanced secretion of CCN2 and S100A9

Skin involvement with dermal fibrosis is a hallmark of systemic sclerosis (SSc), and keratinocytes may be critical regulators of fibroblast function through secretion of chemo-attracting agents, as well as through growth factors and cytokines influencing the phenotype and proliferation rate of fibroblasts. Epithelial-fibroblast interactions have an important role in fibrosis in general. We have characterized the SSc epidermis and asked whether SSc-injured epidermal cells release factors capable of promoting fibrosis. Our results show that the SSc epidermis is hypertrophic, and has altered expression of terminal differentiation markers involucrin, loricrin, and filaggrin. Multiplex profiling revealed that SSc epidermal explants release increased levels of CCN2 and S100A9. CCN2 induction was found to spread into the upper papillary dermis, whereas S100A9 was shown to induce fibroblast proliferation and to enhance fibroblast CCN2 expression via Toll-like receptor 4. These data suggest that the SSc epidermis provides an important source of pro-fibrotic CCN2 and proinflammatory S100A9 in SSc skin, and therefore contributes to the fibrosis and inflammation seen in the disease.

Pig dorsum model for examining impaired wound healing at the skin-implant interface of percutaneous devices

Percutaneous medical devices are indispensable in contemporary clinical practice, but the associated incidence of low to moderate mortality infections represents a significant economic and personal cost to patients and healthcare providers. Percutaneous osseointegrated prosthetics also suffer from a similar risk of infection, limiting their clinical acceptance and usage in patients with limb loss. We hypothesized that transepidermal water loss (TEWL) management at the skin-implant interface may improve and maintain a stable skin-to-implant interface. In this study, skin reactions in a 3-month, pig dorsum model were assessed using standard histology, immunohistochemistry, and quantitative image analysis. Immunohistochemical analysis of peri-implant tissue explants showed evidence of: continuous healing (cytokeratin 6+), hypergranulation tissue (procollagen+), hyper-vascularity (collagen 4+), and the presence of fibrocytes (CD45+ and procollagen type 1+). Importantly, the gross skin response was correlated to a previous load-bearing percutaneous osseointegrated prosthetic sheep study conducted in our lab. The skin responses of the two models indicated a potentially shared mechanism of wound healing behavior at the skin-implant interface. Although TEWL management did not reduce skin migration at the skin-implant interface, the correlation of qualitative and quantitative measures validated the pig dorsum model as a high-throughput platform for translational science based percutaneous interface investigations in the future.

A review of the effects of moisturizers on the appearance of scars and striae

Scars are well known to have a stratum corneum (SC) that is malfunctional. Increases in transepidermal water loss and decreases in SC capacitance and conductance have been reported. Occlusion therapy is a well-known route to improving the signs and symptoms of scarring. Until recently that has been assumed to be totally pressure related. However, studies have demonstrated that the direct effects of hydration on keratinocytes and fibroblasts contribute to the reduction in hypertrophic scarring. Now it is well known that occlusion can regulate epidermal cytokine and growth factor production; changes in profibrotic and anti-fibrotic factors have been established. As a result, it is to be expected that moisturizers may improve the signs and symptoms of scars. As striae have been suggested to be anatomically similar to scars and as it is well established that paracrine signalling occurs in skin, it is expected that striae have similar SC issues. While one cannot exclude the effects of some of the ingredients used in the products, several studies are reported in this review that demonstrates that moisturization is a key component to reducing the clinical signs and symptoms of scars and striae. This is a good example of how knowledge of corneobiology leads to corneotherapies for these skin condition problems. The review is being written in memory of Professor Johann Wiechers who, before he died tragically in November 2011, performed two of the reported studies together with colleagues.