New approach to the understanding of keloid: psychoneuroimmune-endocrine aspects

The Efficacy and Safety of Botulinum Toxin Type A in Prevention of Hypertrophic Scars After Epicanthoplasty: A Split-Face Double-Blinded Randomized Controlled Trial

BACKGROUND

Timely intervention can improve the aesthetic outcome of surgical scars, and botulinum toxin type A (BTXA) has demonstrated its potential as an effective treatment. However, conclusive scientific evidence is needed to definitively confirm the specific efficacy of BTXA following epicanthoplasty.

METHODS

A total of 21 patients who underwent epicanthoplasty were enrolled. Either BTXA or normal saline was randomly injected into the left or right epicanthus immediately after epicanthoplasty. The efficacy of scar prevention was assessed at a 1-month and 6-month follow-up visit using various assessment scales, and scar widths were also measured. The safety assessment included evaluating the complications and adverse effects after injections.

RESULTS

Totally, 20 patients completed the entire follow-up period. At 6-month follow-up, significant improvements were noted (P<0.05) in the treatment group compared to the control group across all evaluated metrics: the Modified Stony Brook Scar Evaluation Scale (total scores: 6.73±1.26 vs 5.75±1.60), Observer Scar Assessment Scale (total scores: 6.35±5.93 vs 8.55±5.65), Patient Scar Assessment Scale (color scores: 1.10±1.17 vs 1.85±1.69), Visual Analog Scale (total scores: 8.48±1.24 vs 7.94±1.37), and the average scar widths (0.37±0.18mm vs 0.68±0.42mm). No adverse effects were observed.

CONCLUSIONS

BTXA can effectively prevent scar hyperplasia after epicanthoplasty, especially in improving scar pigmentation, width, and softness.

LEVEL OF EVIDENCE II

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Commensal microbiome dysbiosis elicits interleukin-8 signaling to drive fibrotic skin disease

Wound healing is an intensely studied topic involved in many relevant pathophysiological processes, including fibrosis. Despite the large interest in fibrosis, the network that is related to commensal microbiota and skin fibrosis remains mysterious. Here, we pay attention to keloid, a classical yet intractable skin fibrotic disease to establish the association between commensal microbiota to scaring tissue. Our histological data reveal the presence of microbiota in the keloids. 16S rRNA sequencing characterizes microbial composition and divergence between the pathological and normal skin tissues. Moreover, the data show elevation of interleukin-8 (IL-8) in both the circulation and keloid tissue, which elicited the collagen accumulation and migratory program of dermal fibroblasts via CXCR1/2 receptor. Our research provides insights into the pathology of human fibrotic diseases, advocating commensal bacteria and IL-8 signaling as useful targets in future interventions of recurrent keloid disease.

An Open-Label, Uncontrolled, Single-Arm Clinical Trial of Tofacitinib, an Oral JAK1 and JAK3 Kinase Inhibitor, in Chinese Patients with Keloid

BACKGROUND

The keloid treatment is still a thorny and complicated clinical problem, especially in multiple keloids induced by wound, severe burn, ethnic background or cultural behaviors, or unexplained skin healing. Mainstream treatments have limited efficacy in treating multiple keloids. As no oral treatment with painlessness and convenience is available, oral treatment strategies should be formulated.

OBJECTIVES

This study aimed to investigate the efficacy and therapeutic mechanism of oral tofacitinib in keloid patients.

METHODS

We recruited the 7 patients with keloid scars and prescribed 5 mg of tofacitinib twice a day orally with a maximum follow-up of 12 weeks. The Patient and Observer Scar Assessment Scale (POSAS), the Vancouver scar scale (VSS), ANTERA 3D camera, and the DUB Skin Scanner 75 were used to assess the characteristics of the lesion. Immunohistochemistry was performed to evaluate collagen synthesis, proliferation, and relative molecular pathways. Moreover, the effects of tofacitinib were assessed on keloid fibroblast in vitro.

RESULTS

After 12 weeks of oral tofacitinib, significant improvement in POSAS, VSS, and Dermatology Life Quality Index (DLQI) scores was observed (p < 0.05). The volume, lesion height, and dermis thickness of the keloid decreased (p < 0.05). Moreover, significant decreases in the expression of collagen I, Ki67, p-STAT 3, and p-SMAD2 were observed after 12 weeks of administration. In vitro experiments suggested that tofacitinib treatment inhibits fibroblast proliferation and collagen I synthesis via suppression of STAT3 and SMAD2 pathway.

CONCLUSION

Tofacitinib, a new candidate oral drug for keloid, could reduce keloid lesion volume by inhibiting collagen synthesis and inhibiting fibroblast proliferation, and alleviate itch and pain to obtain a better life quality.

Electric Factors in Wound Healing

Significance: Electric factors such as electric charges, electrodynamic field, skin battery, and interstitial exclusion permeate wound healing physiology and physiopathology from injury to re-epithelialization. The understanding of how electric factors contribute to wound healing and how treatments may interfere with them is fundamental for the development of better strategies for the management of pathological scarring and chronic wounds. Recent Advances: Angiogenesis, cell migration, macrophage activation hemorheology, and microcirculation can interfere and be interfered with electric factors. New treatments with various types of electric currents, laser, light emitting diode, acupuncture, and weak electric fields applied directly on the wound have been developed to improve wound healing. Critical Issues: Despite the basic and clinical development, pathological scars such as keloids and chronic wounds are still a challenge. Future Directions: New treatments can be developed to improve skin wound healing taking into account the influence of electrical charges. Monitoring electrical activity during skin healing and the influence of treatments on hemorheology and microcirculation are examples of how to use knowledge of electrical factors to increase their effectiveness.

Correlation of Melanin Content with Collagen Density in Keloid Patients

BACKGROUND: Keloid is a form of wound healing that results from fibrous tissue activity. It can develop beyond the boundaries of the original wound, extends into the dermis layer, and disrupting the appearance. Previously, no studies have revealed a correlation between melanin pigment and keloid. AIM: This research aimed to describe the correlation between melanin concentration and collagen deposition in keloid tissue. MATERIALS AND METHODS: A prospective study conducted through the application of a cross-sectional analytic survey method. The color of the skin was measured using a chromameter, and a histopathologic examination was performed on the skin surrounding the keloid, as well as the keloid tissue. Data were analyzed using a t-test, correlation, and linear regression statistics. RESULTS: The results showed a significant difference between melanin concentration and collagen deposition in the skin surrounding the keloid tissue. No significant difference was observed between melanin concentration in the surrounding skin of keloid and those in the keloid tissue, as well as collagen deposition. Meanwhile, the melanin concentration in the surrounding skin of keloid and keloid tissue had a significant relationship with fibrocytes number. CONCLUSION: There is a significant correlation between melanin concentrations and collagen density in the keloid tissue.

Management of keloid scars: noninvasive and invasive treatments

Scars vary from mature linear scars to abnormal excessive scars such as hypertrophic scars and keloid scars. Keloid scars are fibro-proliferative disease entities that reflect an abnormal process of wound healing. They can cause pain, itching, stiffness, and psychological distress, all of which can affect quality of life. Various treatment options have been advocated as ways to prevent and treat keloid scars. These include noninvasive treatments such as use of silicone gel sheeting and compression therapy, and invasive treatments such as intralesional corticosteroid injections, surgery, and radiotherapy. Novel treatments include chemotherapy, immunotherapy, and anti-inflammatory therapies. Unfortunately, keloids continue to pose a significant challenge due to the lack of efficacious treatments. Therefore, clinicians should be familiar with various therapeutic options and apply the most suitable treatment plan for patients. In this review, we introduce the current therapeutic options for the management of keloid scars.

The Keloid Disorder: Heterogeneity, Histopathology, Mechanisms and Models

Keloids constitute an abnormal fibroproliferative wound healing response in which raised scar tissue grows excessively and invasively beyond the original wound borders. This review provides a comprehensive overview of several important themes in keloid research: namely keloid histopathology, heterogeneity, pathogenesis, and model systems. Although keloidal collagen versus nodules and α-SMA-immunoreactivity have been considered pathognomonic for keloids versus hypertrophic scars, conflicting results have been reported which will be discussed together with other histopathological keloid characteristics. Importantly, histopathological keloid abnormalities are also present in the keloid epidermis. Heterogeneity between and within keloids exists which is often not considered when interpreting results and may explain discrepancies between studies. At least two distinct keloid phenotypes exist, the superficial-spreading/flat keloids and the bulging/raised keloids. Within keloids, the periphery is often seen as the actively growing margin compared to the more quiescent center, although the opposite has also been reported. Interestingly, the normal skin directly surrounding keloids also shows partial keloid characteristics. Keloids are most likely to occur after an inciting stimulus such as (minor and disproportionate) dermal injury or an inflammatory process (environmental factors) at a keloid-prone anatomical site (topological factors) in a genetically predisposed individual (patient-related factors). The specific cellular abnormalities these various patient, topological and environmental factors generate to ultimately result in keloid scar formation are discussed. Existing keloid models can largely be divided into in vivo and in vitro systems including a number of subdivisions: human/animal, explant/culture, homotypic/heterotypic culture, direct/indirect co-culture, and 3D/monolayer culture. As skin physiology, immunology and wound healing is markedly different in animals and since keloids are exclusive to humans, there is a need for relevant human in vitro models. Of these, the direct co-culture systems that generate full thickness keloid equivalents appear the most promising and will be key to further advance keloid research on its pathogenesis and thereby ultimately advance keloid treatment. Finally, the recent change in keloid nomenclature will be discussed, which has moved away from identifying keloids solely as abnormal scars with a purely cosmetic association toward understanding keloids for the fibroproliferative disorder that they are.

Topical delivery of 5-fluorouracil-loaded carboxymethyl chitosan nanoparticles using microneedles for keloid treatment

Keloids are induced by skin injuries such as surgeries, skin piercings, burns, and trauma. The intra-lesional injection of 5-fluorouracil (5-FU) is a promising therapy to treat keloid. However, local 5-FU injections have caused several side effects such as pain at administration and hyperpigmentation. This study suggests a safer and more effective 5-FU delivery system. We used microneedles to treat keloid because this method has the feasibility of self-administration without pain. In this study, 5-FU-loaded carboxymethyl chitosan (CMC) nanoparticles were prepared and characterized by various analytical methods and then coated on stainless solid microneedles. The blank CMC nanoparticles caused an increase in cell viability on human normal fibroblasts to 150%. In particular, the 5-FU-loaded CMC nanoparticles showed a significant inhibitory effect on the human keloid fibroblast to 16%. The intercellular uptake of the 5-FU-loaded CMC nanoparticles was observed on both human normal and keloid fibroblasts by using a confocal microscope. In addition, it was found that the nanoparticles showed an inhibition of TGF-β1 by ELISA. For topical drug delivery, it was confirmed that the nanoparticles coated onto the microneedles were dissolved and diffused at the administration site in the porcine dorsal skin model. According to these results, the suggested microneedle-mediated drug delivery system not only inhibits the human keloid fibroblasts by delivering drugs effectively into the keloids but also has the feasibility to self-administer without pain. Therefore, this new system including 5-FU-loaded CMC nanoparticles and microneedles has the potential to treat keloid scars. Graphical abstract.

Immunohistochemical Expression of Cyclooxygenases in Hypertrophic Scars and Keloids

Background:

There are studies demonstrating an increased expression of cyclooxygenase (COX) in keloids and hypertrophic scars, suggesting that anti-inflammatory drugs could be used in their treatment. However, a precise relationship between COX and pathological scarring has not been established in the literature yet. This study aims to evaluate the immunohistochemical expression of COXs in these scars.

Methods:

Prospective study, including 54 patients (aged 18–60 years) undergoing scar excision: 18 normal scars (group 1), 18 hypertrophic scar (group 2), and 18 keloids (group 3). The group classification was performed by clinical criteria. Scars samples were collected and anatomopathological examination (through hematoxylin-eosin method) was performed to confirm the scar type. Immunohistochemistry was performed to assess the expression of COX1 and COX2 in epidermis and dermis. Results were compared among all groups and between group I versus II and III together (abnormal scars).

Results:

For COX1, in the epidermis, there was no significant difference in the immunohistochemical expression when comparing the 3 groups. In the dermis, groups 2 and 3 had greater expression than group 1, with a significant difference being found when comparing all groups (P = 0.014), and in the comparison between normal versus abnormal scars (P = 0.004). For COX2, there was no significant difference between the groups in both the epidermis and dermis.

Conclusions:

The immunohistochemical expression of COX1 was greater in the dermis of abnormal scars when compared with normal scars. Future studies can be performed involving COX blockade as a perspective of these scars treatment.

In vitro analysis of the role of tumor necrosis factor‑stimulated gene‑6 in keloid

An increasing number of studies have demonstrated that tumor necrosis factor-stimulated gene-6 (TSG-6) has a key role in the progression of fibrosis; however, the exact effects of TSG-6 in keloid fibroblasts (KFs) remain unknown. The aim of the current study was to investigate the role of TSG-6 in the pathogenesis of keloids. Primary fibroblasts from 10 patients with keloid were cultured and transfected with pLVX-Puro or pLVX-Puro-TSG-6. Alterations of TSG-6 expression were then determined by reverse transcription-polymerase chain reaction (RT-PCR) and regulation was observed in KFs transfected with pLVX-Puro-TSG-6. Compared with the control group, transfection with pLVX-Puro-TSG-6 induced growth suppression, cell apoptosis and G2/M arrest in KFs. In addition, the mitochondrial apoptosis pathway was activated in KFs transfected with pLVX-Puro-TSG-6. These findings indicate that TSG-6 is a novel regulator of keloid fibrogenesis, and thus could be used/targeted TSG-6 as a promising treatment for keloid.

Keloid risk in patients with atopic dermatitis: a nationwide retrospective cohort study in Taiwan

OBJECTIVE

The pathogenesis of keloid is largely unknown. Because keloid and atopic dermatitis have overlapping pathophysiological mechanisms, we aimed to evaluate keloid risk in patients with atopic dermatitis.

STUDY DESIGN

Population-based retrospective cohort study.

SETTING

The Taiwan National Health Insurance Research Database was used to analyse data for people who had been diagnosed with atopic dermatitis.

PARTICIPANTS

We identified 8371 patients with newly diagnosed atopic dermatitis during 1996-2010. An additional 33 484 controls without atopic dermatitis were randomly identified and frequency matched at a one-to-four ratio.

PRIMARY AND SECONDARY OUTCOME MEASURE

The association between atopic dermatitis and keloid risk was estimated using Cox proportional hazard regression models.

RESULTS

After adjustment for covariates, the atopic dermatitis patients have a 3.19-fold greater risk of developing keloid compared with the non-atopic dermatitis group (3.19vs1.07 per 1000 person-years, respectively). During the study period, 163 patients with atopic dermatitis and 532 patients without atopic dermatitis developed keloid. Notably, keloid risk increased with severity of atopic dermatitis, particularly in patients with moderate to severe atopic dermatitis.

CONCLUSIONS

Our results indicate that patients with atopic dermatitis had a higher than normal risk of developing keloid and suggest that atopic dermatitis may be an independent risk factor for keloid.

Novel Insights on Understanding of Keloid Scar: Article Review

Keloid scar, dermal benign fibro-proliferative growth that extends outside the original wound and invades adjacent dermal tissue due to extensive production of extracellular matrix, especially collagen, which caused by over expression of cytokines and growth factors. Although many attempts were made to understand the exact pathophysiology and the molecular abnormalities, the pathogenesis of keloid scar is yet to be determined. Even though there are several treatment options for keloid scars include combination of medical and surgical therapies like combination of surgical removal followed by cryotherapy or intralesional steroid therapy, the reoccurrence rate is still high despite the present treatment. In this review, PubMed, clinical key and Wright State Library web site have been used to investigate any update regarding Keloid disease. We used Keloid, scar formation, hypertrophic scar and collagen as key words. More than 40 articles have been reviewed. This paper reviews literature about keloid scar formation mechanism, the most recent therapeutic options including the ones under research.