Activation of ERK and p38 kinase mediated keloid fibroblast apoptosis after flashlamp pulsed-dye laser treatment

Early postoperative interventions in the prevention and management of thyroidectomy scars

Thyroidectomy scars, located on the exposed site, can cause distress in patients. Owing to the cosmetic importance of thyroidectomy scars, many studies have been conducted on its prevention and treatment. Scar formation factors mainly include inflammatory cell infiltration, angiogenesis, fibroblast proliferation, secretion of cytokines such as transforming growth factor (TGF)-β1, and mechanical tension on the wound edges. Anti-scar methods including topical anti-scar agents, skin tension-bearing devices, and local injections of botulinum toxin, as well as lasers and phototherapies, that target these scar formation factors have been developed. However, current studies remain fragmented, and there is a lack of a comprehensive evaluation of the impacts of these anti-scar methods on treating thyroidectomy scars. Early intervention is a crucial but often neglected key to control hyperplastic thyroidectomy scars. Therefore, we review the currently adopted early postoperative strategies for thyroidectomy scar reduction, aiming to illustrate the mechanism of these anti-scar methods and provide flexible and comprehensive treatment selections for clinical physicians to deal with thyroidectomy scars.

Tripterine Inhibits Proliferation and Promotes Apoptosis of Keloid Fibroblasts by Targeting ROS/JNK Signaling

Keloids are benign skin tumors characterized by excessive fibroblast proliferation and collagen deposition. The current treatment of keloids with hormone drug injection, surgical excision, radiotherapy, physical compression, laser therapy, cryotherapy often have unsatisfactory outcomes. The phytochemical compounds have shown great potential in treating keloids. Tripterine, a natural triterpene derived from the traditional Chinese medicine Thunder God Vine (Tripterygium wilfordii), was previously reported to exhibit an anti-scarring bioactivity in mouse embryonic fibroblast NIH/3T3 cells. Accordingly, our study was dedicated to explore its role in regulating the pathological phenotypes of keloid fibroblasts. Human keloid fibroblasts were treated with tripterine (0-10 μM) for 24 hours. Cell viability, proliferation, migration, apoptosis, and extracellular matrix (ECM) deposition were determined by CCK-8, EdU, wound healing, Transwell, flow cytometry, western blotting, and RT-qPCR assays. The effects of tripterine treatment on reactive oxygen species (ROS) generation and JNK activation in keloid fibroblasts were assessed by DCFH-DA staining and western blotting analysis. Tripterine at the concentrations higher than 4 μM attenuated the viability of human keloid fibroblasts in a dose-dependent manner. Treatment with tripterine (4, 6, and 8 μM) dose-dependently inhibited cell proliferation and migration, promoted cell apoptosis, reduced α-SMA, Col1, and Fn expression, induced ROS production, and enhanced JNK phosphorylation in keloid fibroblasts. Collectively, tripterine ameliorates the pathological characteristics of keloid fibroblasts that are associated with keloidformation and growth by inducing ROS generation and activating JNK signalingpathway.

Combined CO2 and dye laser technique in the treatment of outcomes due to flap necrosis after surgery for basal cell carcinoma on the nose

BACKGROUND AND OBJECTIVE

Basal cell carcinoma (BCC) is the most frequent cutaneous cancer worldwide, and the nasal area is the most commonly affected region. Skin flaps are usually performed to achieve radical results, but various adverse events often occur. The necrosis of the skin flap is one of the most frequently observed, resulting in scars and anti-aesthetic outcomes. Ablative and non-ablative lasers have been proposed to improve scars resulting from surgical failure and skin flap necrosis.

STUDY DESIGN/MATERIALS AND METHODS

This study aims to evaluate a new laser protocol combining ablative CO₂ -laser with flashlamp pulsed dye laser for the treatment of nasal scars resulting from the necrosis of flap that occurred after surgery. Twelve patients were enrolled in the study, and a total of five laser sessions were planned, spaced from 14 days to 1 month apart.

RESULTS

Seven out of 12 patients underwent all the five laser sessions planned, while 5/12 patients achieved optimal cosmetic results within the fourth session. Eighty percent of the patients reported good/optimal cosmetic results, and no significant side effects were observed during the study.

CONCLUSION

Combining fractionated CO₂ laser with flashlamp pulsed dye laser represents a new effective modality for treating skin flap necrosis after BBC removal, representing a valid alternative to other surgical procedures.

5-Fluorouracil Management of Oculofacial Scars: A Systematic Literature Review

PURPOSE

To review the literature for the safety and efficacy of intralesional 5-fluorouracil (5-FU) in the management of oculofacial scars.

METHODS

A literature search was performed in July 2019 in the PubMed database to identify reports of the use of 5-FU injections for modulating oculofacial cutaneous scars. The search yielded 152 articles, of which 15 met criteria outlined for assessment. Data were abstracted from these 15 relevant articles.

RESULTS

While there were no high-level prospective randomized controlled trials, 8 were lower-quality randomized controlled trial, 3 were retrospective cohort studies, and 4 were case series. Most studies pooled results of facial and nonfacial cutaneous applications. Three studies focused solely on oculofacial applications, and these were all lower-level evidence studies. The study outcomes included scar dimension reduction, erythema, patient satisfaction score, observer assessment of scar improvement, and recurrence rates. 5-Fluorouracil was administered as monotherapy or as part of multimodality treatment with other agents (usually corticosteroids) or with CO2 laser, radiotherapy, or pulsed dye laser. 5-Fluorouracil was usually given as an intralesional injection, but in some studies, it was applied topically after micropuncture of the skin. The number and timing of treatments varied between studies. Overall, the level of safety of 5-FU was high. Pain with injection was the most common reported side effect. Other common adverse side effects included pruritus, telangiectasias, changes in pigmentation, and purpura, and 2 studies noted more serious events, such as ulceration, superficial necrosis, and local infection. There were no severe side effects such as anaphylaxis, immune suppression, secondary malignancy, systemic infection, blindness, or death. In all studies, 5-FU was associated with prophylaxis of oculofacial scars or improvement of keloids or hypertrophic scars in terms of reducing size, erythema, and pruritus. 5-Fluorouracil application was associated with favorable patient satisfaction and observer assessment scores especially compared with corticosteroid injections alone.

CONCLUSIONS

High-quality randomized controlled trials are currently lacking, and the existing literature is predominately not specific to use of 5-FU on the face. These studies, however, suggest that intralesional 5-FU is safe and probably more effective than other options in the management of cutaneous scars in the oculofacial region. The delivery methods, timing, dosing, and concomitant therapies were highly variable. Further high-quality controlled studies specific to oculofacial scars may be indicated to assess the efficacy of 5-FU and to establish the best protocols for administering this medication.

Combination of 1,064-nm Neodymium-doped Yttrium Aluminum Garnet Laser and Steroid Tape Decreases the Total Treatment Time of Hypertrophic Scars: An Analysis of 40 Cases of Cesarean-Section Scars

BACKGROUND

The 1,064-nm neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (Cutera, Inc., Brisbane, CA) and steroid tape (fludroxycortide tape) have been used to treat keloids and hypertrophic scars.

OBJECTIVE

To evaluate the efficacy of contact-mode 1,064-nm Nd:YAG laser therapy and steroid tape for hypertrophic cesarean-section scars versus conservative therapy (steroid tape only).

MATERIALS AND METHODS

A medical record review identified 40 consecutive Japanese patients who had hypertrophic scars (total Japan Scar Workshop Scar Scale [JSS] 2015 evaluation scores of 9 to 12) for more than 1 year after a vertical cesarean section and who were treated at our scar-specialist clinic from July 2015 to December 2017. All 40 patients continued treatment until the total JSS score dropped below 3. Recurrence was defined as a ≥1-point increase in the total JSW score 6 months after achieving a total JSS score <3.

RESULTS

The patients had a mean age of 34.2 years. The test (n = 25) and control (n = 15) groups took on average 16.9 and 24.3 months to achieve a total JSS score <3, respectively (p < .01). In the following 6 months, none of the scars recurred.

CONCLUSION

Nd:YAG laser treatment effectively decreased the total treatment time of hypertrophic cesarean-section scars. An algorithm for treating mild and severe hypertrophic cesarean-section scars is proposed.

Triamcinolone acetonide intralesional injection for the treatment of keloid scars: patient selection and perspectives

Keloids are pathological scars presenting as nodular lesions that extend beyond the area of injury. They do not spontaneously regress, often continuing to grow over time. The abnormal wound-healing process underlying keloid formation results from the lack of control mechanisms self-regulating cell proliferation and tissue repair. Keloids may lead to cosmetic disfigurement and functional impairment and affect the quality of life. Although several treatments were reported in the literature, no universally effective therapy was found to date. The most common approach is intralesional corticosteroid injection alone or in combination with other treatment modalities. Triamcinolone acetonide (TAC) is the most commonly used intralesional corticosteroid. The aim of this article was to review the use of TAC, alone or in combination, in the treatment of keloid scars. The response to corticosteroid injection alone is variable with 50-100% regression and a recurrence rate of 33% and 50% after 1 and 5 years, respectively. Compared to verapamil, TAC showed a faster and more effective response even though with a higher complication rate. TAC combined with verapamil was proved to be effective with statistically significant overall improvements of scars over time and long-term stable results. TAC and 5-fluorouracil (5-FU) intralesional injections were found to achieve comparable outcomes when administered alone, although 5-FU was more frequently associated with side effects. Conversely, the combination of 5-FU and TAC was more effective and showed fewer undesirable effects compared to TAC or 5-FU alone. Several kinds of laser treatments were reported to address keloids; however, laser therapy alone was burdened with a high recurrence rate. Better results were described by combining CO2, pulsed-dye or Nd: YAG lasers with TAC intralesional injections. Further options such as needle-less intraepidermal drug delivery are being explored, but more studies are needed to establish safety, feasibility and effectiveness of this approach.

Low-Level Light Therapy with 410 nm Light Emitting Diode Suppresses Collagen Synthesis in Human Keloid Fibroblasts: An In Vitro Study

Background

Keloids are characterized by excessive collagen deposition in the dermis, in which transforming growth factor β (TGF-β)/Smad signaling plays an important role. Low-level light therapy (LLLT) is reported as effective in preventing keloids in clinical reports, recently. To date, studies investigating the effect of LLLT on keloid fibroblasts are extremely rare.

Objective

We investigated the effect of LLLT with blue (410 nm), red (630 nm), and infrared (830 nm) light on the collagen synthesis in keloid fibroblasts.

Methods

Keloid fibroblasts were isolated from keloid-revision surgery samples and irradiated using 410-, 630-, 830-nm light emitting diode twice, with a 24-hour interval at 10 J/cm². After irradiation, cells were incubated for 24 and 48 hours and real-time quantitative reverse transcription polymerase chain reaction was performed. Western blot analysis was also performed in 48 hours after last irradiation. The genes and proteins of collagen type I, TGF-β1, Smad3, and Smad7 were analyzed.

Results

We observed no statistically significant change in the viability of keloid fibroblasts after irradiation. Collagen type I was the only gene whose expression significantly decreased after irradiation at 410 nm when compared to the non-irradiated control. Western blot analysis showed that LLLT at 410 nm lowered the protein levels of collagen type I compared to the control.

Conclusion

LLLT at 410 nm decreased the expression of collagen type I in keloid fibroblasts and might be effective in preventing keloid formation in their initial stage.

Nonconventional Use of Flash-Lamp Pulsed-Dye Laser in Dermatology

Flash-lamp pulsed-dye laser (FPDL) is a nonablative technology, typically used in vascular malformation therapy due to its specificity for hemoglobin. FPDL treatments were performed in a large group of patients with persistent and/or recalcitrant different dermatological lesions with cutaneous microvessel involvement. In particular, 149 patients (73 males and 76 females) were treated. They were affected by the following dermatological disorders: angiokeratoma circumscriptum, genital and extragenital viral warts, striae rubrae, basal cell carcinoma, Kaposi's sarcoma, angiolymphoid hyperplasia, and Jessner-Kanof disease. They all underwent various laser sessions. 89 patients (59.7%) achieved excellent clearance, 32 patients (21.4%) achieved good-moderate clearance, 19 patients (12.7%) obtained slight clearance, and 9 subjects (6.1%) had low or no removal of their lesion. In all cases, FPDL was found to be a safe and effective treatment for the abovementioned dermatological lesions in which skin microvessels play a role in pathogenesis or development. Further and single-indication studies, however, are required to assess a standardized and reproducible method for applying this technology to “off-label” indications.

Keloids and Hypertrophic Scars: A Spectrum of Clinical Challenges

Since their earliest description, keloids and hypertrophic scars have beleaguered patients and clinicians alike. These scars can be aesthetically disfiguring, functionally debilitating, emotionally distressing, and psychologically damaging, culminating in a significant burden for patients. Our current understanding of keloid pathophysiology has grown and continues to advance while molecular biology, genetics, and technology provide ever-deepening insight into the nature of wound healing and the pathologic perturbations thereof. Greater understanding will lead to the development and application of refined therapeutic modalities. This article provides an overview of our current understanding of keloids, highlighting clinical characteristics and diagnostic criteria while providing a comprehensive summary of the many therapeutic modalities available. The proposed mechanism, application, adverse events, and reported efficacy of each modality is evaluated, and current recommendations are summarized.

Longitudinal, 3D Imaging of Collagen Remodeling in Murine Hypertrophic Scars In Vivo Using Polarization-Sensitive Optical Frequency Domain Imaging

Hypertrophic scars (HTS), frequently seen after traumatic injuries and surgery, remain a major clinical challenge because of the limited success of existing therapies. A significant obstacle to understanding HTS etiology is the lack of tools to monitor scar remodeling longitudinally and noninvasively. We present an in vivo, label-free technique using polarization-sensitive optical frequency domain imaging for the 3D, longitudinal assessment of collagen remodeling in murine HTS. In this study, HTS was induced with a mechanical tension device for 4-10 days on incisional wounds and imaged up to 1 month after device removal; an excisional HTS model was also imaged at 6 months after injury to investigate deeper and more mature scars. We showed that local retardation and degree of polarization provide a robust signature for HTS. Compared with normal skin with heterogeneous local retardation and low degree of polarization, HTS was characterized by an initially low local retardation, which increased as collagen fibers remodeled, and a persistently high degree of polarization. This study demonstrates that polarization-sensitive optical frequency domain imaging offers a powerful tool to gain significant biological insights into HTS remodeling by enabling longitudinal assessment of collagen in vivo, which is critical to elucidating HTS etiology and developing more effective HTS therapies.

A thermosensitive hydroxybutyl chitosan hydrogel as a potential co-delivery matrix for drugs on keloid inhibition

A thermosensitive hydroxybutyl chitosan hydrogel could be used as a potential co-delivery matrix for drugs on keloid inhibition.

Laser scar management technique

BACKGROUND AND AIMS

Scars are common and cause functional problems and psychological morbidity. Recent advances in optical technologies have produced various laser systems capable of revising the appearance of scars from various etiologies to optimize their appearance.

METHODS

Laser treatment can commence as early as the time of the initial injury and as late as several years after the injury. Several optical technologies are currently available and combined laser/light treatments are required for treatment of scars. Since 2006, we have set up a scar management department in our clinic and more than 2000 patients have been treated by our combined laser irradiation techniques. Herein, we review several available light technologies for treatment of surgical, traumatic, and inflammatory scars, and discuss our combined laser treatment of scars, based upon our clinical experience.

RESULTS AND CONCLUSIONS

Because scars have a variety of potential aetiologies and take a number of forms, no single approach can consistenty provide good scar treatment and management. The combination of laser and devices is essential, the choice of wavelength and approach being dictated by each patient as an individual.

Effect of FK506 in reducing scar formation by inducing fibroblast apoptosis after sciatic nerve injury in rats

We previously demonstrated that FK506, a generally applied immunosuppressant in organ transplantation, could promote peripheral nerve regeneration through reducing scar formation. However, little is known about how FK506 reduces scar formation. Herein we investigated the influence of FK506 on fibroblast proliferation and its correlation with scar formation after sciatic nerve injury in rats, and further explored the effect of FK506 on fibroblast proliferation and apoptosis in vitro. Masson staining and immunohistochemistry revealed that scar area and fibroblast number in the nerve anastomosis of sciatic nerve-injured rats were significantly reduced after FK506 administration. The scar area had a significant positive correlation with the fibroblast number, as detected by linear correlation analysis. CCK-8 assay and flow cytometry indicated that FK506 also inhibited proliferation and induced apoptosis of fibroblasts in vitro. It was primarily phosphorylation of JNK and ERK that were activated during the apoptosis of fibroblast. Pretreatment of cells with JNK inhibitor, SP600125, or ERK inhibitor, PD98059, could inhibit FK506-induced fibroblast apoptosis, respectively. Moreover, simultaneous application of both inhibitors had additive roles in cell protection from apoptosis. These results suggest that FK506-induced fibroblast apoptosis contributes to the suppression of fibroblast proliferation and then results in the reduction of scar formation in sciatic nerve-injured rat, and that JNK and ERK are involved in FK506-induced fibroblast apoptosis.

Keloids can be forced into remission with surgical excision and radiation, followed by adjuvant therapy

We have treated keloids using a combination of surgical excision and postoperative irradiation. The objective of this study was to evaluate the results of our treatment over 12 years. From 1995 until 2006, we treated keloids using the aforementioned treatment. If we identified a sign of recurrence during the follow-up period, we started an intralesional injection of triamcinolone acetonide immediately. We selected 91 keloids for which we had more than 2 years of follow-up data for this study and assessed the results according to our original scale (Kyoto scar scale) based on objective and subjective symptoms. In all, 51 keloids (56.0%) were cured completely by a combination of surgical excision and postoperative irradiation without additional treatment, and finally 81 keloids (89.0%) showed good results with additional treatment. Keloids are a controllable condition when treated with combination therapy, involving surgical excision with postoperative irradiation and early conservative treatment after the detection of recurrence.

Acne scars: pathogenesis, classification and treatment

Acne has a prevalence of over 90% among adolescents and persists into adulthood in approximately 12%-14% of cases with psychological and social implications. Possible outcomes of the inflammatory acne lesions are acne scars which, although they can be treated in a number of ways, may have a negative psychological impact on social life and relationships. The main types of acne scars are atrophic and hypertrophic scars. The pathogenesis of acne scarring is still not fully understood, but several hypotheses have been proposed. There are numerous treatments: chemical peels, dermabrasion/microdermabrasion, laser treatment, punch techniques, dermal grafting, needling and combined therapies for atrophic scars: silicone gels, intralesional steroid therapy, cryotherapy, and surgery for hypertrophic and keloidal lesions. This paper summarizes acne scar pathogenesis, classification and treatment options.

Pulsed dye laser-induced inflammatory response and extracellular matrix turnover in rat vocal folds and vocal fold fibroblasts

BACKGROUND AND OBJECTIVES

Disruption of the vocal fold extracellular matrix (ECM) can induce a profound and refractory dysphonia. Pulsed dye laser (PDL) irradiation has shown early promise as a treatment modality for disordered ECM in patients with chronic vocal fold scar; however, there are limited data addressing the mechanism by which this laser energy might induce cellular and extracellular changes in vocal fold tissues. In this study, we examined the inflammatory and ECM modulating effects of PDL irradiation on normal vocal fold tissues and cultured vocal fold fibroblasts (VFFs).

STUDY DESIGN/MATERIALS AND METHODS

We evaluated the effects of 585 nm PDL irradiation on inflammatory cytokine and collagen/collagenase gene transcription in normal rat vocal folds in vivo (3-168 hours following delivery of approximately 39.46 J/cm(2) fluence) and VFFs in vitro (3-72 hours following delivery of 4.82 or 9.64 J/cm(2) fluence). We also examined morphological vocal fold tissue changes 3 hours, 1 week, and 1 month post-irradiation.

RESULTS

PDL irradiation altered inflammatory cytokine and procollagen/collagenase expression at the transcript level, both in vitro and in vivo. Additionally, PDL irradiation induced an inflammatory repair process in vivo that was completed by 1 month with preservation of normal tissue morphology.

CONCLUSIONS

PDL irradiation can modulate ECM turnover in phenotypically normal vocal folds. Additional work is required to determine if these findings extend to disordered ECM, such as is seen in vocal fold scar. Lasers Surg. Med. 41:585-594, 2009. (c) 2009 Wiley-Liss, Inc.

Cutaneous scarring: a clinical review

Cutaneous scarring can cause patients symptoms ranging from the psychological to physical pain. Although the process of normal scarring is well described the ultimate cause of pathological scarring remains unknown. Similarly, exactly how early gestation fetuses can heal scarlessly remains unsolved. These questions are crucial in the search for a preventative or curative antiscarring agent. Such a discovery would be of enormous medical and commercial importance, not least because it may have application in other tissues. In the clinical context the assessment of scars is becoming more sophisticated and new physical, medical and surgical therapies are being introduced. This review aims to summarise some of the recent developments in scarring research for non-specialists and specialists alike.

Extracorporeal shock-wave therapy enhanced wound healing via increasing topical blood perfusion and tissue regeneration in a rat model of STZ-induced diabetes

Extracorporeal shock-wave therapy (ESWT) has a significant positive effect in accelerating chronic wound healing. However, the bio-mechanisms operating during ESWT of wounds remain unclear. This study investigated the effectiveness of ESWT in the enhancement of diabetic wound healing. A dorsal skin defect (area, 6 x 5 cm) in a streptozotocin-induced diabetes rodent model was used. Fifty male Wistar rats were divided into five groups. Group I consisted of nondiabetic control; group II included diabetic control receiving no ESWT; group III included rats that underwent one session of ESWT (ESW-1) on day 3 (800 impulses at 0.09 mJ/mm(2)) postwounding; group IV included rats that underwent two sessions of ESWT (ESW-2) on days 3 and 7; and group V included rats that underwent three sessions of ESWT (ESW-3) on days 3, 7, and 10. The wound healing was assessed clinically. Blood perfusion scan was performed with laser Doppler. The VEGF, eNOS, and PCNA were analyzed with immunohistochemical stain. The results revealed that the wound size was significantly reduced in the ESWT-treated rats, especially in the ESW-2 and ESW-3 groups, as compared with the control (p<0.01). Blood perfusion was significantly increased after ESWT compared with the controls. Histological findings revealed a significant reduction in the topical pro-inflammatory reaction in the ESWT group as compared with the control. In immunohistochemical stain, significant increases in VEGF, eNOS, and PCNA expressions were observed in the ESWT group, especially in the ESW-2 and ESW-3 groups, as compared with the control. In conclusion, treatment with an optimal session of ESWT significantly enhanced diabetic wound healing associated with increased neo-angiogenesis and tissue regeneration, and topical anti-inflammatory response.

Hypertrophic scars and keloids--a review of their pathophysiology, risk factors, and therapeutic management

BACKGROUND

Hypertrophic scars and keloids result from an abnormal fibrous wound healing process in which tissue repair and regeneration-regulating mechanism control is lost. These abnormal fibrous growths present a major therapeutic dilemma and challenge to the plastic surgeon because they are disfiguring and frequently recur.

OBJECTIVE

To provide updated clinical and experimental information on hypertrophic scars and keloids so that physicians can better understand and properly treat such lesions.

METHODS

A Medline literature search was performed for relevant publications and for diverse strategies for management of hypertrophic scars and keloids.

CONCLUSION

The growing understanding of the molecular processes of normal and abnormal wound healing is promising for discovery of novel approaches for the management of hypertrophic scars and keloids. Although optimal treatment of these lesions remains undefined, successful healing can be achieved only with combined multidisciplinary therapeutic regimens.

Prevention and management of hypertrophic scars and keloids after burns in children

Hypertrophic scars and keloids are challenging to manage, particularly as sequelae of burns in children in whom the psychologic burden and skin characteristics differ substantially from adults. Prevention of hypertrophic scars and keloids after burns is currently the best strategy in their management to avoid permanent functional and aesthetical alterations. Several actions can be taken to prevent their occurrence, including parental and children education regarding handling sources of fire and flammable materials, among others. Combination of therapies is the mainstay of current burn scar management, including surgical reconstruction, pressure therapy, silicon gels and sheets, and temporary garments. Other adjuvant therapies such as topical imiquimod, tacrolimus, and retinoids, as well as intralesional corticosteroids, 5-fluorouracil, interferons, and bleomycin, have been used with relative success. Cryosurgery and lasers have also been reported as alternatives. Newer treatments aimed at molecular targets such as cytokines, growth factors, and gene therapy, currently in developing stages, are considered the future of the treatment of postburn hypertrophic scars and keloids in children.

Green tea polyphenol epigallocatechin-3-gallate suppresses collagen production and proliferation in keloid fibroblasts via inhibition of the STAT3-signaling pathway

Keloids are benign skin tumors characterized by collagen accumulation and hyperproliferation of fibroblasts. To find an effective therapy for keloids, we explored the pharmacological potential of (-)-epigallocatechin-3-gallate (EGCG), a widely investigated tumor-preventive agent. When applied to normal and keloid fibroblasts (KFs) in vitro, proliferation and migration of KFs were more strongly suppressed by EGCG than normal fibroblast proliferation and migration (IC(50): 54.4 microM (keloid fibroblast (KF)) versus 63.0 microM (NF)). The level of Smad2/3, signal transducer and activator of transcription-3 (STAT3), and p38 phosphorylation is more enhanced in KFs, and EGCG inhibited phosphorylation of phosphatidylinositol-3-kinase (PI3K), extracellular signal-regulated protein kinase 1/2 (ERK1/2), and STAT3 (Tyr705 and Ser727). To evaluate the contribution of these pathways to keloid pathology, we treated KFs with specific inhibitors for PI3K, ERK1/2, or STAT3. Although a PI3K inhibitor significantly suppressed proliferation, PI3K and MEK/ERK inhibitors had a minor effect on migration and collagen production. However, a JAK2/STAT3 inhibitor and a STAT3 siRNA strongly suppressed proliferation, migration, and collagen production by KFs. We also found that treatment with EGCG suppressed growth and collagen production in the in vivo keloid model. This study demonstrates that EGCG suppresses the pathological characteristics of keloids through inhibition of the STAT3-signaling pathway. We propose that EGCG has potential in the treatment and prevention of keloids.

Flashlamp pulsed-dye laser suppressed TGF-beta1 expression and proliferation in cultured keloid fibroblasts is mediated by MAPK pathway

BACKGROUND AND OBJECTIVES

Our previous clinical study indicated that transforming growth factor-beta1 (TGF-beta1) and mitogen-activated protein kinases (MAPK) are both involved in keloid regression following flashlamp pulsed-dye laser (PDL). To further characterize of this involvement, this work examined whether PDL suppression of TGF-beta1 expression was mediated through MAPK pathway in cultured keloid fibroblasts (KF).

STUDY DESIGN/MATERIALS AND METHODS

Primary culture of KF harvested from keloid patients received various dosages of PDL treatment in 585-nm wavelength. TGF-beta1 expressions in KF following various dosages of PDL were assessed. Additionally, MAPK pathway activities were studied using the PD98059 (an ERK inhibitor), SB203580 (a p38 kinase inhibitor), and SP600125 (a JNK inhibitor), to determine the role in keloid following PDL treatment. Activator protein-1 (AP-1), a transcription factor of TGF-beta, was analyzed by electrophoretic mobility shift assay (EMSA). Phosphorylated c-Jun, one of the components of AP-1, was also detected.

RESULTS

The observation results demonstrated that optimal dosages of PDL significantly suppressed KF proliferation and TGF-beta1 expression. EMSA study identified PDL downregulation of super-shift of AP-1. Three subtypes of MAPK cascades were augmented between 30 minutes and 4 hours following PDL treatment, particularly phosphorylation of ERK1/2 and p38. Pre-treatment with PD98059, SB203580, but not SP600125, markedly inhibited the downregulating effects of TGF-beta1 and phosphorylated c-Jun expression following PDL treatment.

CONCLUSION

PDL induced keloid regression is mediated by triggering MAPK cascades and blockade of AP-1 transcription and TGF-beta expression. Modulation of TGF-beta and MAPK interaction in keloids may provide specific targets for therapeutic intervention.

Abnormal wound healing: keloids

Wound healing is a complex and carefully regulated physiologic response to a traumatic injury. Deregulation of this coordinated process can lead to exuberant scar formation as seen in keloids and hypertrophic scars. Despite their common occurrence, keloids remain one of the most challenging dermatologic conditions to successfully treat and may have significant psychosocial impact for the patient. In this review, we discuss the clinical features, genetics, epidemiology, and treatment of keloids.

Laser treatment of keloids and hypertrophic scars

BACKGROUND

Lasers have been used in the treatment of hypertrophic scars and keloids for more than 20 years. Different laser systems have been examined; among them pulsed dye lasers are currently considered the laser of choice in these settings.

OBJECTIVES

The purpose of this study is to review the pertinent literature and provide updated information on different laser therapies available for treatment of keloids and hypertrophic scars.

METHODS

A Medline literature search was performed for relevant publications.

RESULTS

In this review the results of published studies in the treatment and prevention of hypertrophic scars and keloids are presented. Suggested mechanisms of action are reviewed. A review of the optimal laser parameters to modulate treatment outcome will be discussed. Different lasers are effective in not only the treatment but also the prevention of hypertrophic scars and keloids, among them PDL is more promising. Most of the suggested theories are based on the selective photothermolysis in which the light energy emitted from a vascular laser is absorbed by hemoglobin, generating heat and leading to coagulation necrosis, neocollagenesis, collagen fiber heating with dissociation of disulfide bonds and subsequent collagen fiber realignment.

CONCLUSION

The optimal laser is currently 585 nm PDL, although the recent results of Q-switched 532 nm frequency-doubled Nd:YAG are promising. Early use of lasers are beneficial, especially in those who are prone to develop these lesions.

Keloids and scars: a review of keloids and scars, their pathogenesis, risk factors, and management

PURPOSE OF REVIEW

The precise mechanisms of normal and abnormal scar formation have long remained a mystery despite the extensive literature regarding wound healing. Only recently have researchers begun to delineate the complex biochemical signaling pathways that regulate these processes. This article reviews basic wound healing, while focusing on medicine's latest understanding of the development and treatment of keloids and hypertrophic scars.

RECENT FINDINGS

The importance of the transforming growth factor-beta signaling pathways and the related downstream effector molecules has proven to offer a new detailed view of scar biology. Regulation of scar metabolism with regards to collagen and wound matrix degradation is likewise showing promise in generating alternate therapies to treat abnormal scars.

SUMMARY

Understanding the exact process of normal and abnormal scar formation will help define better ways to successfully manage and potentially prevent abnormal healing like hypertrophic scars and keloids.

Dexamethasone Induction of Keloid Regression through Effective Suppression of VEGF Expression and Keloid Fibroblast Proliferation

The biological mechanism underlying steroid therapy for treating keloids remains unclear. Analytical results demonstrated that topical intra-lesional steroid injections suppress vascular endothelial growth factor (VEGF) expression in keloid tissue and induce its regression in vivo. This study investigated whether glucocorticoid (dexamethasone) downregulates VEGF expression and hinders keloid fibroblast (KF) proliferation in keloid regression. Primary KF cultures were treated with various concentrations of dexamethasone, glucocorticoid receptor (GR) antagonist (mifeprostone, RU-486), VEGF-A antibody, VEGF receptor-2 (VEGF-R2) antagonist (SU-5416), and VEGF protein. Analytical results demonstrated that dexamethasone retarded KFs proliferation. However, suppression of fibroblast proliferation by dexamethasone pre-treatment was reduced by adding exogenous VEGF protein. Dexamethasone suppressed endogenous VEGF mRNA induction, protein expressed by KFs, and angiogenesis activity detected by a tube-forming assay of human umbilical vein endothelial cells co-cultured fibroblasts. These effects were reversed by pre-treatment with RU-486, and not by pre-treatment with SU-5416. Thus, dexamethasone induces keloid regression via interaction with the GR and suppresses endogenous VEGF expression and fibroblast proliferation. However, exogenous VEGF promotes fibroblast proliferation through the GR-independent pathway. Modulation of VEGF production may comprise a valuable treatment modality for keloids.

The keloid phenomenon: Progress toward a solution

For centuries, keloids have been an enigma and despite considerable research to unravel this phenomenon no universally accepted treatment protocol currently exists. Historically, the etiology of keloids has been hypothesized by multiple different theories; however, a more contemporary view postulates a multifactoral basis for this disorder involving nutritional, biochemical, immunological, and genetic factors that play a role in this abnormal wound healing. Critical to the process of preventing or managing keloids is the need to locally control fibroblasts and their activities at the wound site. In recent years, considerable evidence has accumulated demonstrating the importance of fatty acids and bioactive lipids in health and disease, especially those involving inflammatory disorders or immune dysfunction. If hypertrophic scarring and keloid formation can be argued to have significant inflammatory histories, then it is possible to postulate a role for lipids in their etiology and potentially in their treatment. This report briefly visits past views and theories on keloid formation and treatment, and offers a theoretical rationale for considering adjuvant fatty acid therapy for keloid management. Sufficient scientific evidence in support of fatty acid strategies for the prevention and treatment of keloids currently exists, which offer opportunities to bridge the gap between the laboratory and the clinic. The intent of this paper is to serve as a basic guideline for researchers, nutritionists, and clinicians interested in keloids and to propose new directions for keloid management.

Scar management: prevention and treatment strategies

PURPOSE OF REVIEW

Aberrant wound healing results in unsightly scar, hypertrophic scar, and keloid formation, causing functional and cosmetic deformities, discomfort, psychological stress, and patient dissatisfaction. Scar prevention and management, both surgical and nonsurgical, continue to be important issues for the otolaryngologist.

RECENT FINDINGS

Both animal and human models continue to point to the integral role of transforming growth factor-beta in aberrant healing. Multiple extracts have promising results as therapies for scarring and are widely marketed but need to be further investigated. Scar prevention advancements include refinements in surgical technique, nutritional supplementation, and optimal wound care. Steroid injections continue to play a major role in the regression of scars and keloids. Dermatography assists in the minimization of scar appearance. Dermatography, laser therapies, intralesional 5-fluorouracil, and adjuvant radiotherapy are emerging therapies. Topical vitamin E utility is revisited. New surgical scar revision techniques include modified excision techniques and skin grafting.

SUMMARY

Despite optimal efforts to avoid scar formation, aberrant wound healing may occur. The use of topical agents and intralesional steroid injections can minimize early scar formation. Strategies for prevention and management of keloids and hypertrophic scars continue to develop, as the basic science mechanisms underlying aberrant wound healing are elucidated.