Hypertrophic scar

Application of 3D Transparent Facemasks in Long-Term Outpatient Rehabilitation of Facial Scars After Burns: A Retrospective Cohort Study of Improved Appearance of Target Scars With Different Healing Time

Severe facial burns may cause scarring problems and affect living quality of patients. With the advent of 3D facemasks, it is being used to treat facial scars; however, its efficacy must be confirmed by adequate studies. A retrospective analysis of 26 patients who visited rehabilitation outpatient clinic from 2017 to 2022. Patients were separated into two groups based on the time to healing (TTH) following burn injury: early healing group (TTH ≤ 21 days) and late healing group (TTH > 21 days). To compare treatment outcomes and differences between the two groups, 3D facemask application was assessed using the Vancouver Scar Scale (VSS), patient satisfaction, and complications. In both groups, there were significant improvements in the total VSS scores (P < .01) and each VSS subscore (P < .01). These scar characteristics improved over time as the treatment progressed. Compared with the late healing group, the early healing group had more obvious effects on improving scar pigmentation (P < .05) and vascularity (P < .05) at similar assessment time points after burns. At the last assessment, there was a significant difference in total VSS scores between groups (P = .009). For the early and late healing groups, respectively, the mean gradient value (SE) of the total VSS scores was 1.550 (0.373) and 1.283 (0.224) over the course of the treatment periods. 3D facemasks are effective in the rehabilitation of facial scars caused by burns, which should be used for prevention and treatment in the initial stages of scar development.

Mechanical Micronization of Lipoaspirates Combined with Fractional CO 2 Laser for the Treatment of Hypertrophic Scars

BACKGROUND

Treating hypertrophic scars remains challenging. Stromal vascular fraction (SVF) gel is produced by a purely mechanical process from lipoaspirates, rich in adipose-derived stem cells, and has showed therapeutic potential on scars. However, controversial effects on hypertrophic scars are emerging. This study aimed to assess the therapeutic effects of SVF gel combined with fractional CO 2 laser on hypertrophic scars.

METHODS

A rabbit ear hypertrophic scar model was established. SVF gel combined with fractional CO 2 laser was conducted for hypertrophic scars in rabbits. Scar alleviation in rabbits was observed based on the appearance and histology of scars, and the underlying mechanism was investigated by tissue immunologic analyses and quantitative real time polymerase chain reaction. At last, six patients with hypertrophic scar were treated by SVF gel combined with fractional CO 2 laser. Therapeutic effects were assessed using the Vancouver Scar Scale.

RESULTS

Following the treatments, hypertrophic scars became less apparent and softer, the dermis became thinner, and collagen fibers appeared looser and arranged in a more organized pattern. The SVF gel plus fractional CO 2 laser group showed the most obvious improvement. In addition, SVF gel combined with fractional CO 2 laser increased adipogenesis in scar tissue, and adipose tissue regeneration was observed. Hypertrophic scars in patients were alleviated after treatment with SVF gel combined with fractional CO 2 laser.

CONCLUSIONS

SVF gel transplantation combined with fractional CO 2 laser showed encouraging therapeutic effects on hypertrophic scars. Although further investigation is necessary, this technique has great potential for clinical application to treat hypertrophic scars.

CLINICAL RELEVANCE STATEMENT

This is a new technique for treating hypertrophic scars.

Evaluation of Clinical and Biomechanical Features of Scars Resulting from the Treatment of Burn Contractures Comparing Acellular Dermal Matrices: A Randomized Clinical Trial

OBJECTIVE

The aim of this study was to compare clinical and biomechanical features of scars resulting from the treatment of burn contractures using different acellular dermal matrices (ADM).

SUMMARY BACKGROUND DATA

Extensive burns often lead to severe sequelae, such as skin contractures, that can be treated using ADM to improve the quality of these scars.

METHODS

A prospective, randomized and controlled clinical trial was performed including patients with burn contractures at least 1-year post-burn, treated using split-thickness skin graft (STSG). These patients were randomized into 4 groups: control (received only STSG without ADM), Integra (ADM + STSG), Matriderm (ADM + STSG), and Pelnac (ADM + STSG). Exclusion criteria were loss of follow-up and graft integration failure. The evaluation was performed using the Vancouver Scar Scale (VSS), the durom-eter, and the cutometer in areas of normal skin, hypertrophic scar, and surgical scar, at least 1 year after the surgery.

RESULTS

In the VSS, durometer, and cutometer evaluation, there was no difference in the comparison of surgical scars among groups. Analyzing each group, with an intraindividual evaluation comparing areas of normal skin with surgical scars, the results suggested a possibility of a surgical scar hardness closer to normal skin for Integra and Matriderm groups measured with the durometer. In the cutometer evaluation, surgical scars were not comparable to areas of normal skin.

CONCLUSIONS

This study suggests that there is no difference in the quality of scar assessed through the analysis of clinical and biomechanical features comparing acellular dermal matrices (Integra, Matriderm, and Pelnac) and only split-thickness skin graft without a dermal matrix.

β-Elemene induces apoptosis by activating the P53 pathway in human hypertrophic scar fibroblasts

BACKGROUND

Hypertrophic scar (HS) is a condition characterized by excessive synthesis and deposition of collagen. There are many clinical methods to alleviate HS, but most of them are accompanied by many complications.

AIM OF THE STUDY

To investigate the effects of β-Elemene, extracted from the ginger family plant Wenyujin, on Human hypertrophic scar fibroblast.

MATERIALS AND METHODS

Cultured human hypertrophic scar fibroblast (hHSFs) and human normal fibroblasts (HF), and observed the effect of β-Elemene on apoptosis、extracellular matrix and endoplasmic reticulum stress by Western blot、RT-PCR and flow cytometry.

RESULTS

Based on our findings, it is clear that β-Elemene could inhibit the expression of α-SMA、collagen I and Fibronectin, reduced collagen deposition. Further studies had found that β-Elemene could increase the expression of endoplasmic reticulum stress (ERS)-related proteins CHOP and Calnexin in a dose-dependent manner, thereby promoting the aggregation of cleaved-caspase-3 and inducing hHSFs to undergo apoptosis. This process may depend on the regulation of P53.

CONCLUSIONS

The results of our study indicates that β-Elemene induced hHSFs to undergo apoptosis though ERS pathway in a P53-dependent manner, which means that our research provided a new strategy for the development of drugs for the treatment of HS. This article is protected by copyright. All rights reserved.

LncRNA PICSAR binds to miR-485-5p and activates TGF-β1/Smad to promote abnormal proliferation of hypertrophic scar fibroblasts (HSFs) and excessive deposition of extracellular matrix (ECM)

The purpose of this study is to explore whether LncRNA PICSAR binds to miR-485-5p and thereby activates TGF-β1/Smad signaling pathway, influencing the abnormal proliferation of fibroblasts and excessive deposition of ECM in hypertrophic scar formation. PICSAR and miR-485-5p expressions were detected by qPCR. Cell proliferation was examined by CCK-8. Protein expressions were determined by western blot. Immunofluorescence detected the Ki-67 expression. Dual-luciferase followed by immunoprecipitation was performed to verify the interaction between PICSAR and miR-485-5p. Interference with PICSAR inhibited the abnormal proliferation of hypertrophic scar fibroblasts (HSFs) and the excessive deposition of ECM. It was also confirmed in our study that MiR-485-5p is a direct target of PICSAR in HSFs. Additionally, inhibition of miR-485-5p reversed the effect of PICSAR knockdown in HSFs. LncRNA PICSAR binds to miR-485-5p and thereby activates TGF-β1/Smad signaling pathway, promoting the abnormal proliferation of fibroblasts and excessive deposition of ECM in hypertrophic scar formation.

Comparison of Nd: YAG Laser and Combined Intense Pulsed Light and Radiofrequency in the Treatment of Hypertrophic Scars: A Prospective Clinico-Histopathological Study

INTRODUCTION

Hypertrophic scars are fibroproliferative disorders, seen after burn, trauma, and/or surgery. We aimed to compare the clinical and histopathological results of 1064-nm Nd:YAG laser and combined intense pulsed light and radiofrequency in the treatment of hypertrophic scars.

METHODS

Fifty patients with hypertrophic scars were included in this prospective, randomized study. Twenty-five patients were treated with Nd:YAG laser and 25 patients with combined intense pulsed light and radiofrequency (E-light). The scars were evaluated at baseline, during and at 3 months after the final treatment session using the Vancouver scar scale. Biopsy specimens from scars were obtained before, during, and 3 months after the final treatment session and were stained with hematoxylin and eosin stain, Masson's trichrome stain, and immunostaining procedures for collagen I, collagen III, and TGF-β1.

RESULTS

Significant improvements in the total Vancouver scar scale scores before and after the treatment in both groups (P < 0.001); however, a significant difference between both groups (P < 0.001), regarding the E-light, which showed better response than Nd:YAG laser. Hematoxylin and eosin and Masson's trichrome staining showed arrangement and thinning of collagen bundles and reduction in collagen density by in both groups, but the collagen bundles thinning and parallelism were more obvious in the E-light group. Significant decrease in the concentration of collagen I, collagen III, and TGF-β1 in the E-light group as compared with the laser group (P = 0.005, P = 0.003 and P < 0.001, respectively).

CONCLUSIONS

Both modalities were successful in the treatment of hypertrophic scars; however, a significant improvement in the clinical and histopathological findings was detected with the E-light method.

Programmable immune activating electrospun fibers for skin regeneration

Immune cells play a crucial regulatory role in inflammatory phase and proliferative phase during skin healing. How to programmatically activate sequential immune responses is the key for scarless skin regeneration. In this study, an "Inner-Outer" IL-10-loaded electrospun fiber with cascade release behavior was constructed. During the inflammatory phase, the electrospun fiber released a lower concentration of IL-10 within the wound, inhibiting excessive recruitment of inflammatory cells and polarizing macrophages into anti-inflammatory phenotype "M2c" to suppress excessive inflammation response. During the proliferative phase, a higher concentration of IL-10 released by the fiber and the anti-fibrotic cytokines secreted by polarized "M2c" directly acted on dermal fibroblasts to simultaneously inhibit extracellular matrix overdeposition and promote fibroblast migration. The "Inner-Outer" IL-10-loaded electrospun fiber programmatically activated the sequential immune responses during wound healing and led to scarless skin regeneration, which is a promising immunomodulatory biomaterial with great potential for promoting complete tissue regeneration.

Adding herbal extracts to silicone gel on post-sternotomy scar: a prospective randomised double-blind study

OBJECTIVE

Silicone gel has been shown effective in improving healing post-sternotomy scars. It remains to be determined whether adding herbal extracts to the gel would augment the healing effect.

METHOD

After median sternotomy, patients were randomised into two groups. Group 1: topical silicone gel plus herbal extract gel (Allium cepa, Centella Asiatica, Aloe vera and Paper Mulberry) and Group 2: silicone gel. Patients were treated for six months. The postoperative scars were assessed at three and six months by plastic surgeons using the Vancouver Scar Scale (VSS) and the patient assessment scar scale.

RESULTS

Each group comprised 23 patients (n=46 in total). The VSS was significantly lower in Group 1 than in Group 2 (p=0.018 and p=0.051, respectively). In Group 1, the four differences from baseline were vascularity scores at three and six months (-0.391, p=0.025; -0.435, p=0.013, respectively), and pigmentation scores at three and six months (-0.391, p=0.019; -0.609, p=0.000, respectively). In Group 2, differences from baseline were the pigmentation and vascularity score at six months (-0.6609, p=0.000; -0.348, p=0.046, respectively).

CONCLUSION

Our results suggest, post-sternotomy scars trend to have better vascularity and pigmentation when treated with silicone gel plus herbal extracts.

MicroRNA-497-5p downregulation inhibits cell viability, reduces extracellular matrix deposition and induces apoptosis in human hyperplastic scar fibroblasts by regulating Smad7

Hypertrophic scars (HSs) are characterized by excessive extracellular matrix deposition and excessive growth of dense fibrous tissues. MicroRNAs (miRNAs/miRs) serve key roles in HS formation. The present study investigated the expression, role and mechanism underlying the effects of miR-497-5p in HS formation. miR-497-5p expression was detected via reverse transcription-quantitative PCR. The association between miR-497-5p and Smad7 was analyzed using TargetScan and luciferase reporter assays. Protein expression levels of extracellular matrix markers were measured via western blotting. Cell viability and apoptosis were determined using the Cell Counting Kit-8 assay and flow cytometry, respectively. The results suggested that miR-497-5p expression was upregulated in HS tissues and human HS fibroblasts (hHSFs) compared with healthy control skin tissues and CCC-ESF-1 cells, respectively. Smad7 was directly targeted by miR-497-5p, and was downregulated in HS tissues and hHSFs compared with healthy control skin tissues and CCC-ESF-1 cells, respectively. Moreover, Smad7 upregulation significantly inhibited cell viability, decreased extracellular matrix deposition and induced apoptosis in hHSFs compared with the control-plasmid group. Moreover, the results indicated that, compared with the inhibitor control group, miR-497-5p inhibitor inhibited cell viability, decreased extracellular matrix deposition and induced apoptosis in hHSFs, which were significantly reversed by Smad7 knockdown. In conclusion, the results indicated that miR-497-5p downregulation repressed HS formation by inhibiting extracellular matrix deposition and hHSF proliferation at least partly by targeting Smad7.

MiR-3613-3p inhibits hypertrophic scar formation by down-regulating arginine and glutamate-rich 1

Hypertrophic scar (HS) is a severe skin disorder characterized by excessive extracellular matrix production and abnormal function of fibroblasts. Recent studies have demonstrated that microRNAs (miRNAs) play critical roles in HS formation. This study aims to investigate the role of miR-3613-3p in the formation of HS. The mRNA and miRNA levels were measured by quantitative RT-PCR analysis. The protein levels were examined by Western blot assay. Cell proliferation was determined by Cell Counting Kit-8 assay. The Caspase-3 and Caspase-9 activities were measured using flow cytometry assay. Dual-luciferase activity reporter assay and mRNA-miRNA pulldown assay were conducted to validate the target of miR-3613-3p. miR-3613-3p was downregulated, while arginine and glutamate-rich 1 (ARGLU1) was upregulated in HS fibroblasts (HSFs) and tissues. Overexpression of miR-3613-3p or knockdown of ARGLU1 markedly inhibited the expression of extracellular matrix (ECM) production-associated proteins and promoted Caspase-3 and Caspase-9 activations in HSFs. ARGLU1 was further identified as a direct target of miR-3613-3p. Restoration of ARGLU1 abrogated the suppressive effect of miR-3613-3p on cell proliferation and ECM protein expression of HSFs. Our results demonstrated that miR-3613-3p inhibited HS formation via targeting ARGLU1, which may provide potential therapeutic targets for the management of HS.

A Prospective Randomized Double-blind study of silicone gel plus Herbal Extracts Versus Placebo in Pre-sternal hypertrophic scar prevention and amelioration

Objective

Post-surgical hypertrophic scar is more frequently reported in Asians. Many modalities can treat scars but there have not been any publications to define the efficacy of silicone gel plus herbal extracts for scar prevention or amelioration.

Design

48 patients, who underwent median sternotomy were randomized and double-blinded to 2 groups to use topical silicone gel plus herbal extract gel or placebo for 6 months. Patients were treated either with topical silicone gel plus herbal extract gel or control using only placebo for 6 months. The scars were observed by experienced plastic surgeons using the Vancouver scar scale.

Setting

A single tertiary care center at Khon Kaen University.

Paticipants

48 patients who underwent median sternotomy were enrolled in this study. All patients were aged over 18 years. All the wounds were sutured with polyglycolic 4/0 subcuticular suture material and did not receive other scar management before participating in this study.

Intervention

The silicone gel plus herbal extract gel (Bangkok Botanica, Bangkok, Thailand) in semi-liquid form was formulated from 15% Herbal extract (Allium Cepa extract, Centella Asiatica extract, Aloe Vera extract and Paper Mulberry extract), 50% polydemethysiloxane, 30% cyclopentasiloxane and 5% silica. The placebo gel was a composite of water, acrylate, C10-30 alkyl acrylate cross-polymer, polysorbate 20 and fragrance that was similar in color and consistency as that of the active gel and packed in the similar sealed packages.

Main outcome measures

The scar was assessed using the Vancouver scar scale to determine pigmentation, vascularity, pliability and height.

Results

the study showed the silicone gel plus herbal extract gel could improve scar amelioration in height (p = 0.005) and pliability (p < 0.001) when compared to the placebo. The vascularity and pigmentation showed improvement using silicone gel plus herbal extracts but the improvement was not statistically significant.

Conclusion

The silicone gel plus herbal extracts gel was effective for scar improvement in median sternotomy wounds.

Bone marrow concentrate-induced mesenchymal stem cell conditioned medium facilitates wound healing and prevents hypertrophic scar formation in a rabbit ear model

Background

Hypertrophic scars (HSs) are formed via an aberrant response to the wound healing process. HSs can be cosmetic or can result in functional problems. Prolonged proliferation and remodeling phases disrupt wound healing, leading to excessive collagen production and HS formation. However, there are currently no satisfactory drugs to prevent HS formation. Mesenchymal stem cell (MSC) conditioned medium (CM) has therapeutic effects on wound healing and preventing HS formation. Bone marrow concentrate (BMC) contains various growth factors and cytokines that are crucial for regeneration and has been applied in the clinical setting. In this study, we evaluated the effects of BMC-induced MSC CM on HS formation in a rabbit ear model.

Methods

We established a rabbit ear wound model by generating full-thickness wounds in the ears of rabbits (n = 12) and treated wounds with MSC CM, BMC CM, or BMC-induced MSC CM. Dermal fibroblasts from human hypertrophic scar were stimulated with transforming growth factor beta 1 (TGF-β1) for 24 h and cultured in each culture medium for 72 h. We measured the hypertrophic scar (HS) formation during the skin regeneration by measuring the expression of several remodeling molecules and the effect of these conditioned media on active human HS fibroblasts.

Results

Our results showed that BMC-induced MSC CM had greater antifibrotic effects than MSC CM and BMC CM significantly attenuated HS formation in rabbits. BMC-induced MSC CM accelerated wound re-epithelization by increasing cell proliferation. Additionally, BMC-induced MSC CM also inhibited fibrosis by decreasing profibrotic gene and protein expression, promoting extracellular matrix turnover, inhibiting fibroblast contraction, and reversing myofibroblast activation.

Conclusions

BMC-induced MSC CM modulated the proliferation and remodeling phases of wound healing, representing a potential wound healing agent and approach for preventing HS formation.

Electronic supplementary material

The online version of this article (10.1186/s13287-019-1383-x) contains supplementary material, which is available to authorized users.

Effect of pressure therapy for treatment of hypertrophic scar

BACKGROUND

Pressure therapy (PST) has been reported for the treatment of hypertrophic scar (HS) effectively. However, no study has assessed its effect and safety systematically. Therefore, this study will investigate its effect and safety for patients with HS.

METHODS

A comprehensive literature search will be performed from the electronic databases and grey literatures. The electronic databases include MEDILINE, EMBASE, Cochrane Library, Web of Science, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. All of them will be searched from inception to the present without language restrictions. Any randomized controlled trials on assessing the effect and safety of PST on HS will be considered for inclusion. In addition, we will also search grey literature to avoid missing any potential studies. RevMan V.5.3 software will be utilized for statistical analysis.

RESULTS

This study will provide the most recent evidence of PST on HS by evaluating primary outcomes of scar pruritus and improvement of scar; and secondary outcomes of scar blood flow, elasticity, volume, pain and burning. In addition, we will also evaluate adverse events.

CONCLUSION

This study will provide up-to-date evidence of PST in patients with HS.Systematic review registration: PROSPERO CRD42019136627.

Effect of N-(2-aminoethyl) ethanolamine on hypertrophic scarring changes in vitro: Finding novel anti-fibrotic therapies

Hypertrophic scars (HS) limit movement, decrease quality of life, and remain a major impediment to rehabilitation from burns. However, no effective pharmacologic therapies for HS exist. Here we tested the in vitro anti-fibrotic effects of the novel chemical N-(2-aminoethyl) ethanolamine (AEEA) at non-toxic concentrations. Scanning electron microscopy showed that AEEA markedly altered the structure of the extracellular matrix (ECM) produced by primary dermal fibroblasts isolated from a HS of a burn patient (HTS). Compression atomic force microscopy revealed that AEEA stiffened the 3D nanostructure of ECM formed by HTS fibroblasts. Western blot analysis in three separate types of primary human dermal fibroblasts (including HTS) showed that AEEA exposure increased the extractability of type I collagen in a dose- and time-dependent fashion, while not increasing collagen synthesis. A comparison of the electrophoretic behavior of the same set of samples under native and denaturing conditions suggested that AEEA alters the 3D structure of type I collagen. The antagonization effect of AEEA to TGF-β1 on ECM formation was also observed. Furthermore, analyses of the anti-fibrotic effects of analogs of AEEA (with modified pharmacophores) suggest the existence of a chemical structure-activity relationship. Thus, AEEA and its analogs may inhibit HS development; further study and optimization of analogs may be a promising strategy for the discovery for effective HS therapies.

MicroRNA expression signature and the therapeutic effect of the microRNA‑21 antagomir in hypertrophic scarring

Hypertrophic scars (HS) area fibroproliferative disorder of the skin, which causes aesthetic and functional impairment. However, the molecular pathogenesis of this disease remains largely unknown and currently no efficient treatment exists. MicroRNAs (miRNAs) are involved in a variety of pathophysiological processes, however the role of miRNAs in HS development remains unclear. To investigate the miRNA expression signature of HS, microarray analysis was performed and 152 miRNAs were observed to be differentially expressed in HS tissue compared with normal skin tissues. Of the miRNAs identified, miRNA‑21 (miR‑21) was significantly increased in HS tissues and hypertrophic scar fibroblasts (HSFBs) as determined by reverse transcription‑quantitative polymerase chain reaction analysis. It was also observed that, when miR‑21 in HSFBs was blocked through use of an antagomir, the phenotype of fibrotic fibroblasts in vitro was reversed, as demonstrated by growth inhibition, induction of apoptosis and suppressed expression of fibrosis‑associated genes collagen type I α 1 chain (COL1A1), COL1A2 and fibronectin. Furthermore, miR‑21 antagomir administration significantly reduced the severity of HS formation and decreased collagen deposition in a rabbit ear HS model. The total scar area and scar elevation index were calculated and were demonstrated to be significantly decreased in the treatment group compared with control rabbits. These results indicated that the miR‑21 antagomir has a therapeutic effect on HS and suggests that targeting miRNAs may be a successful and novel therapeutic strategy in the treatment of fibrotic diseases that are difficult to treat with existing methods.

Patient opinion of scarring is multidimensional: An investigation of the POSAS with confirmatory factor analysis

INTRODUCTION

Scarring is a significant consequence for patients following a burn. Understanding how patients perceive the physiological scar and define scar severity may provide valuable information regarding how the scar influences quality of life after burn. The Patient and Observer Scar Assessment Scale was the first scar assessment tool validated to include the patients' evaluation of the scars physical qualities, following a burn. Validation studies of this tool have previously been conducted for a discrete scar-site after burn. The aim of this study was to assess the structural validity of the POSAS to capture the patients' evaluation of the total area of burn scar(s).

METHOD

Statistical analysis was based on 508 completed POSAS forms from 358 patients. Exploratory factor analysis (EFA) was used initially to identify the number of factors within the tool, then confirmatory factor analysis (CFA) using structural equation modelling explored areas of misfit within each factor and whether the model provided a predicable structure to capture patient perception of scar severity.

RESULTS/DISCUSSION

The CFA analysis confirmed that a two dimensional model was superior to a unidimensional model when assessing the patient opinion of their total burn scar. The two dimensions were the physical scar (color, stiffness, thickness and irregularity) and the sensory scar (pain and itch). Further strain analysis of the two factor model identified additional domains. Independent factors influenced the perception of color forming a separate subdomain within the physical domain. Color is a visual characteristic, whereas the other three are predominantly tactile characteristics. A significant relationship between thickness and irregularity suggested they may form another subdomain, however further research is required to confirm this. Both pain and itch were recognized as independent, multidimensional latent variables, which require assessment tools with multidimensional structures.

CONCLUSIONS

When assessing the entire burn scar, three independent dimensions influence patient perception: (1) the physical scar, (2) pain and (3) itch. Within the physical domain, color formed a visual subdomain separate to a tactile subdomain. Further development of these domains within a high-order multi-dimensional structure is recommended.

Hypoxic conditioned medium of placenta-derived mesenchymal stem cells protects against scar formation

AIMS

Scar formation after wound repair affects people's daily life. Mesenchymal stem cells were reported to have a beneficial role in attenuating the scar formation. In the present study, placenta-derived mesenchymal stem cells (PMSCs) were isolated and the effects of hypoxic conditioned medium of PMSCs on scar formation were explored.

MAIN METHODS

To evaluate the effect of hypoxia on PMSCs, proliferation of PMSCs was detected by trypan blue staining and the HIF-1α level was detected by western blot. Then in vivo scar formation assay was performed and the histopathologic changes were evaluated by HE staining and levels of TGF-β1 and collagen I were detected by quantitative real-time PCR. The IL-10 level was detected by ELISA and then migration of HFF-1 cells was detected by wound healing assay after treatment with IL-10 or IL-10 antibody.

KEY FINDINGS

Our study showed that hypoxic conditioned medium of PMSCs reduced scar formation in vivo and inhibited the proliferation and migration of skin fibroblasts in vitro. Further mechanism study showed that, the level of IL-10 was affected by hypoxia, treatment with IL-10 mimicked the function of hypoxic conditioned medium of PMSCs and inhibition of IL-10 reversed the protective role of hypoxic conditioned medium of PMSCs. Thus, hypoxic conditioned medium of PMSCs may perform the protective role against scar formation through IL-10.

SIGNIFICANCE

Our study reveals a possible mechanism of the protective effect of PMSCs against scar formation and provides evidence for the hypothesis that PMSCs may be a promising therapy for the treatment of wounds.

Measuring the impact of burn scarring on health-related quality of life: Development and preliminary content validation of the Brisbane Burn Scar Impact Profile (BBSIP) for children and adults

INTRODUCTION

No burn-scar specific, health-related quality of life (HRQOL) measure exists. This study aimed to develop a patient-reported, evaluative HRQOL measure to assess the impact of burn scarring in children and adults.

METHOD

Semi-structured interviews, content validation surveys, and cognitive interviews were used to develop and test content validity of a new measure - the Brisbane Burn Scar Impact Profile (BBSIP).

RESULTS

Participants comprised Australian adults (n=23) and children (n=19) with burn scarring; caregivers of children with burn scarring (n=28); and international scar management experts (n=14). Items distinct from other burn scar measures emerged. Four versions of the BBSIP were developed; one for children aged 8-18 years, one for adults, one for caregivers (as proxies for children aged less than 8-years), and one for caregivers of children aged 8-18 years. Preliminary content validity of the BBSIP was supported. Final items covered physical and sensory symptoms; emotional reactions; impact on social functioning and daily activities; impact of treatment; and environmental factors.

CONCLUSION

The BBSIP was developed to assess burn-scar specific HRQOL and will be available at http://www.coolburns.com.au under a creative commons license. Further testing is underway.

Regeneration of skin tissue promoted by mesenchymal stem cells seeded in nanostructured membrane

BACKGROUND

The mesenchymal stem cell therapy has proven to be an effective option in the treatment of skin injuries. The combination of these cells with nanostructured membranes seems to be the future for tissues recovery. The aim of this project was to use biomolecules of polysaccharides to be incorporated on regenerated cellulose membranes and to prospect the improvement as bioactive wound dressings with mesenchymal stem cells.

METHODS

The biocomposites were obtained after defibrillation with the use of never-dried bacterial cellulose to form a pulp, and, after the films were regenerated, in the presence of gellan gum with or without fluconazole. Membrane atomic force microscopy was performed for comparison of their structures.

RESULTS

Adipose-derived mesenchymal stem cells were obtained from human adipose tissue liposuction in accordance with Zuk et al. The flow cytometric analysis and induction tests for adipocytes and osteocytes were performed. In vitro assays were performed on different membranes to evaluate the ability of these cells to adhere at 2 hours and proliferate at 7 days; the results were obtained by use of the MTT cell counting technique. In vivo testing allowed us to observe cell migration and participation in wound-healing by fluorescence labeling of the cells with BrdU. The bioactive curative, seeded with cells, was tested in skin burned in a murine model.

CONCLUSIONS

The bacterial cellulose with gelan gum membrane incorporated with fluconazole presented the best performance in adhesion and proliferation tests. The cells can be identified in burned host tissue after occurrence of the wound.

iTRAQ-based proteomic profiling reveals different protein expression between normal skin and hypertrophic scar tissue

BACKGROUND

A hypertrophic scar is a unique fibrotic disease that only exists in humans. Despite advances in burn care and rehabilitation, as well as progress in the management during these decades, the hypertrophic scar remains hard to cure following surgical methods and drugs for treatment. In this study, we are looking forward to finding the multitude of possible traumatic mechanisms and the underlying molecular signal ways in the formation of the hypertrophic scar.

METHODS

We used isobaric tags for relative and absolute quantitation (iTRAQ) labeling technology, followed by high-throughput 2D LC-MS/MS, to determine relative quantitative differential proteins between the hypertrophic scar and normal skin tissue.

RESULTS

A total of 3166 proteins were identified with a high confidence (≥95 % confidence). And, a total of 89 proteins were identified as the differential proteins between the hypertrophic scar and normal skin, among which 41 proteins were up-regulated and 48 proteins were down-regulated in the hypertrophic scar. GO-Analysis indicated the up-regulated proteins were involved in extracellular matrix, whereas the down-regulated proteins were involved in dynamic junction and structural molecule activity.

CONCLUSIONS

In our study, we demonstrate 89 proteins present differently in the hypertrophic scar compared to normal skin by iTRAQ technology, which might indicate the pathologic process of hypertrophic scar formation and guide us to propose new strategies against the hypertrophic scar.

Investigating the potential of Shikonin as a novel hypertrophic scar treatment

Background

Hypertrophic scarring is a highly prevalent condition clinically and results from a decreased number of apoptotic fibroblasts and over-abundant production of collagen during scar formation following wound healing. Our previous studies indicated that Shikonin, an active component extracted from Radix Arnebiae, induces apoptosis and reduces collagen production in hypertrophic scar-derived fibroblasts. In the study reported here, we further evaluate the potential use of Shikonin as a novel scar remediation therapy by examining the effects of Shikonin on both keratinocytes and fibroblasts using Transwell® co-culture techniques. The underlying mechanisms were also revealed. In addition, effects of Shikonin on the expression of cytokines in Transwell co-culture “conditioned” medium were investigated.

Results

Our results indicate that Shikonin preferentially inhibits cell proliferation and induces apoptosis in fibroblasts without affecting keratinocyte function. In addition, we found that the proliferation-inhibiting and apoptosis-inducing abilities of SHI might be triggered via MAPK and Bcl-2/Caspase 3 signalling pathways. Furthermore, SHI has been found to attenuate the expression of TGF-β1 in Transwell co-cultured “conditioned” medium.

Conclusions

The data generated from this study provides further evidence that supports the potential use of Shikonin as a novel scar remediation therapy.

Mesenchymal stem cell-mediated suppression of hypertrophic scarring is p53 dependent in a rabbit ear model

Introduction

Mesenchymal stem cells (MSCs) are considered to play important roles in wound repair and tissue remodeling. Hypertrophic scar (HTS) is a cutaneous condition characterized by deposits of excessive amount of collagen after an acute skin injury. However, currently there is little knowledge about the direct relationship between MSCs and HTS.

Methods

The hypertrophic scar model was established on rabbit ears. MSCs were isolated from rabbit femur bone marrow and transplanted through ear artery injection. Hypertrophic scar formation was examined using frozen-section analysis, hematoxylin and eosin (HE) staining, Masson’s trichrome staining, and scar elevation index. The role of p53 in the MSCs-mediated anti-scarring effect was examined by gene knockdown using p53 shRNA.

Results

In this study, MSCs engraftment through ear artery injection significantly inhibited the hypertrophic scarring in a rabbit ear hypertrophic scar model, while this anti-scarring function could be abrogated by p53 gene knockdown in MSCs. Additionally, we found that MSCs down-regulated the expression of TGF-β receptor I (TβRI) and alpha-smooth muscle actin (α-SMA) at both mRNA and protein levels in a paracrine manner, and this down-regulation was rescued by p53 gene knockdown. Moreover, our results showed that MSCs with p53 gene knockdown promoted the proliferation of fibroblasts through increasing nitric oxide (NO) production.

Conclusions

These results suggest that MSCs inhibit the formation of HTS in a p53 dependent manner through at least two mechanisms: inhibition of the transformation of HTS fibroblast to myofibroblast; and inhibition of the proliferation of fibroblasts through inhibition of NO production.

Mechanical tension promotes skin nerve regeneration by upregulating nerve growth factor expression

This study aimed to explore the role of mechanical tension in hypertrophic scars and the change in nerve density using hematoxylin-eosin staining and S100 immunohistochemistry, and to observe the expression of nerve growth factor by western blot analysis. The results demonstrated that mechanical tension contributed to the formation of a hyperplastic scar in the back skin of rats, in conjunction with increases in both nerve density and nerve growth factor expression in the scar tissue. These experimental findings indicate that the cutaneous nervous system plays a role in hypertrophic scar formation caused by mechanical tension.

Fibrosing connective tissue disorders of the skin: molecular similarities and distinctions

A variety of fibrosing connective tissue disorders of the skin have been described. They all share a characteristic activation of fibroblasts resulting in excessive production and deposition of extracellular matrix whereas their etiologies, incidence rates and clinical appearances differ dramatically in part. As effective treatment options are still not on hand, the understanding of cutaneous fibrogenesis needs to be improved. This review focuses on the molecular differences and similarities of the major fibrosing skin disorders namely systemic sclerosis, localized scleroderma, keloid and hypertrophic scars, Eosinophilic fasciitis, Lichen sclerosus and graft-versus-host-disease. Abnormalities in ECM turnover and the impact of matrix-metalloproteases were closely examined. It could be concluded, that besides increased collagen synthesis, modified ECM degradation is an as important factor in cutaneous fibrogenesis. The influence of immune components such as HLA haplotypes and the production of auto-antibodies is crucial for some of the diseases, but not decisive for skin fibrosis in general. A great number of cytokines was reported to be differentially regulated in the respective disorders among whom the components of the gp130/STAT3 signaling pathway seem to be of pivotal importance. Furthermore, the role of miRNAs in the pathogenesis of fibrosing connective tissue diseases of the skin was analyzed according to the current state of knowledge. In summary, this review gives an explicit overview of the various molecular mechanisms leading to fibrosis in the skin and the underlying connective tissue and reveals the most promising targets for future therapeutic approaches.