Dong Kyun Rah’s research while affiliated with Yonsei University Hospital and other places

Purpose: Relaxin (RLX) is a transforming growth factor-β1 (TGF-β1) antagonist that is believed to function as a potent collagen re-arranger and a major suppressor of extracellular matrix components. Adenoviruses (Ads) are accepted vectors for cancer gene therapy. However, repeated treatments of Ad are limited by short-term biological activity in vivo. The efficacy of sustained RLX expression to scar remodeling was assessed using an injectable alginate gel-matrix system. Materials and methods: Pig scar tissue was treated with relaxin-expressing Ad loaded in alginate gel (gel/Ad-RLX). Surface areas, color, and pliability of scars were compared, and various factors influencing scar formation and collagen arrangement were analyzed. Results: Gel/Ad-RLX decreased scar size, color index, and pliability. Immunohistochemistry showed decreased levels of major extracellular matrix proteins in the gel/Ad-RLX-treated group. Furthermore, treatment with gel/Ad-RLX reduced expression of tissue inhibitor of metalloproteinase-1 and alpha-smooth muscle actin and markedly increased expression of matrix metalloproteinase-1 in pig scar tissues. Gel/Ad-RLX also significantly downregulated TGF-β1 and upregulated TGF-β3 mRNAs in pig scar tissues. Conclusion: These results support a prominent role for RLX in scar remodeling and suggest that gel/Ad-RLX may have therapeutic effects on scar formation.

Background:Ischemia-reperfusion (I/R) injury is a leading cause of surgical skin flap compromise and organ dysfunction. Platelet-rich plasma (PRP) is an abundant reserve of various growth factors. Activated platelets play a role in endothelial damage during I/R injury; however, exogenous PRP could inhibit the production of reactive oxygen species. The goal of this study was to investigate the effect of PRP on I/R injury. Methods:Four groups (n=30) of C57BL/6N mice with lateral thoracic artery island flaps were used. Group A, the control group, received flap elevation and repositioning. Group B received PRP and repositioning. Group C had 4 hours of ischemia and then were reperfused. Group D received PRP, had 4 hours of ischemia, and then were reperfused. The survival area of flap tissue and blood perfusion were assessed. Histological evaluation included neutrophil counts. Reactive oxygen species and proinflammatory cytokines were measured to evaluate I/R injury. Protein expression of phosphorylated apoptosis signaling regulating kinase-1 (pASK-1), p38MAPK, and pNF-κB was measured by western blot. Results:PRP treatment enhanced the survival area and perfusion of the flap, reduced neutrophil accumulation in mice subjected to I/R injury. PRP treatment also showed a protective effect, with decreases in nitric oxide, myeloperoxidase, malondialdehyde concentrations. Additionally, PRP suppresses monocyte chemotactic protein-1, TNF-α, IL-1β, and IL-6. Finally, PRP decreased ASK-1 and NF-κB expression in tissues with I/R injury. Conclusion:PRP acts as a protective factor during flap I/R injury by reducing reactive oxygen species level and proinflammatory cytokines via decreased expression of pASK-1 and pNF-κB.

Background Relaxin is a transforming growth factor β1 antagonist. To determine the effects of relaxin on scar reduction, we investigated the scar remodeling process by injecting relaxin-expressing adenoviruses using a pig scar model. Methods Scars with full thickness were generated on the backs of Yorkshire pigs. Scars were divided into two groups (relaxin [RLX] and Control). Adenoviruses were injected into the RLX (expressing relaxin) and Control (not expressing relaxin) groups. Changes in the surface areas, color index and pliability of scars were compared. Results Fifty days after treatment, the surface areas of scars decreased, the color of scars was normalized, and the pliability of scars increased in RLX group. Conclusion Relaxin-expressing adenoviruses improved the surface area, color, and pliability of scars. The mechanism of therapeutic effects on scar formation should be further investigated.

Heat shock protein 90 is a chaperone molecule that aids in proper folding of target proteins. Recently, heat shock protein 90 was found to play a role in would healing through regulation of fibroblast functions. The aim of the present study was to investigate the role of heat shock protein 90 in collagen synthesis in human dermal fibroblasts. The effects of transforming growth factor-β, 17-N-allylamino-17-demethoxygeldanamycin, and transfection of heat shock protein 90 were evaluated by real-time PCR, western blot, and immunofluorescence assays. The Smad 2/3 and Akt pathways were evaluated to identify the signaling pathways involved in collagen synthesis. Heat shock protein 90 and collagen levels were compared in keloid and control tissues by immunohistochemical analysis. The expression of collagen was significantly increased after treatment with transforming growth factor-β, while 17-N-allylamino-17-demethoxygeldanamycin inhibited transforming growth factor-β-induced collagen synthesis. Overexpression of heat shock protein 90 itself with or without transforming growth factor-β increased collagen synthesis. These effects were dependent on Smad 2/3 pathway signaling. Finally, expression of heat shock protein 90 was increased in keloid tissue compared with control tissues. Taken together, these results demonstrate that modulation of heat shock protein 90 influences transforming growth factor-β-induced collagen synthesis via regulation of Smad 2/3 phosphorylation.

Background The treatment of gynecomastia depends on multiple factors, and the best modality is controversial. In this study, we aimed to determine the best management approach by comparing outcomes of two groups of patients with gynecomastia who received subcutaneous mastectomy combined with liposuction and liposuction only. Methods We conducted a retrospective analysis of 64 patients who underwent surgery for gynecomastia. We divided the patients into two groups: group A, patients who underwent liposuction only; and group B, patients who underwent liposuction and subcutaneous mastectomy. The serial photographs of all patients were clinically evaluated with respect to size, shape, scarring, and overall outcome by three plastic surgeons, and patient satisfaction was surveyed with regard to palpable lumps, size, shape, scarring, and overall outcome. ResultsOf the 64 subjects, 16 received liposuction only, and 48 received the combination procedure. A total of 125 breasts were involved. The doctors? scores for size and overall outcome were significantly better in the combination group, whereas scarring was better in the liposuction-only group. Similarly, patient satisfaction regarding size was significantly higher in the combination group, and satisfaction regarding scarring was significantly higher in the liposuction-only group. The scores for scarring in the combination treatment group were acceptable. Conclusion Our study shows that combination treatment with liposuction and subcutaneous mastectomy results in satisfactory outcomes, including the extent of scarring. We conclude that this combination treatment should be recommended as the standard surgical treatment for gynecomastia and can provide excellent results in cases where glandular tissue needs to be removed. Level of Evidence VThis 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.

Red ginseng is well known for its angiogenic effects and its effect of increasing expression of vascular endothelial growth factors (VEGFs), but little experimental evidence has been published. In this study, we examined the effect of red ginseng using an ischemic flap model. Twenty male Sprague-Dawley rats were divided into two groups of 10. One group drank red ginseng solution from 7 days prior to surgery to 7 days after, whereas the other group drank distilled water. We created a local flap on the back of each rat. We analyzed the surviving area of the flap for 10 days after surgery and measured the blood flow of the flap. Ten days after the operation, CD31-positive vessels and VEGF expression were examined by immunohistochemistry. The percentages of surviving areas of the flap were 76 ± 3% for the experimental group and 39 ± 5% for the control group (P = 0.0002). Blood flow in the experimental group increased for 10 days after the surgery. The number of newly generated capillaries in the experimental group was 14.0 ± 3.5, which was significantly higher than 5.7 ± 1.9 in the control group. The expression of VEGF in the experimental group was significantly higher than in the control group (p = 0.0003). Administration of red ginseng extract increases the survival of ischemic flaps via angiogenesis and elevated blood flow. Further clinical studies are warranted to apply the effect shown in this current investigation to various ischemic conditions.

Background Narrow and chubby pretarsal fullness is a characteristic of attractiveness and youthfulness, and pretarsal augmentation has gained popularity in Asia. Conventional lower blepharoplasty has focused on correcting the aged appearance of the lower eyelids by repositioning fat and removing excess skin. However, this technique can create flat lower eyelids and provide an indication that cosmetic surgery was performed. Therefore, our pretarsal augmented lower blepharoplasty technique focuses on restoring pretarsal fullness and creating a three-dimensional lower eyelid-cheek complex. The authors present the results of this technique, which demonstrate that it simultaneously enhances lower eyelid support and restores pretarsal fullness. Methods This retrospective chart review evaluated 659 consecutive patients who underwent pretarsal augmented lower blepharoplasty between 2011 and 2014. All procedures were performed by a single surgeon (H.L.C.). The outcomes and complications were assessed by evaluating the patients’ preoperative and postoperative digital photographs and medical records. Results There were no permanent major complications, such as retrobulbar hemorrhage, diplopia, or hypertrophic scarring. Chemosis occurred in 90 patients (13.7 percent), 10 patients (1.5 percent) underwent minor revision because of an undercorrected nasojugal groove or loosened orbicularis oculi muscle suspension suture, and three patients (0.46 percent) experienced mild ectropion that resolved spontaneously. Approximately 98 percent of the patients were satisfied. Our technique provided a natural and younger appearance with pretarsal fullness, rather than the flattened appearance that is associated with conventional blepharoplasty. Conclusions Pretarsal augmented lower blepharoplasty uses simple methods to restore pretarsal fullness. This technique improves periorbital contouring, rejuvenates the pretarsal roll, and provides excellent aesthetic results. CLINICAL QUESTION/LEVEL OF EVIDENCE Therapeutic, IV.

Recent advances on preclinical model based on patient-derived tumor xenografts have new insight into many clinical fields. According to our literature review, many authors believe that immunodeficient animals such as athymic rats and mice should be used to prevent tissue loss caused by acute rejection to establish patient-derived tumor xenografts models.However, recent advances showed that the microenvironment has gained attention as an important factor responsible for disease progression. Additionally, researchers attempt to come up with novel findings in chemotherapy drugs and immune modulator to control development of keloid. For these reasons, establishment of reliable animal model of keloids is very important.In this new model using an immunocompetent animal as a humanized-xenografts model, human keloid scar has been maintained for as long as 4 months. Results of migration assay have demonstrated that typical morphology of keloid fibroblast was preserved based on multiple time point observations despite its aging change. Quantitative real time polymerase chain reactio findings suggested that after implantation, there has been significant increase of vascular endothelial growth factor, CD34, and transforming growth factor beta 1 expression despite insignificant changes of hypoxia inducible factor 1 an matrix metallopeptidase 1, and matrix metallopeptidase 9 gene expression. These findings suggested that implantation of keloids within the immunocompetent animals yields is very useful experimental model in terms of fibrosis.In summary, the authors have successfully established and propagated patient-derived keloid model using the immunocompetent animals. This model could be used to test novel materials as well as combination therapies and is superior to the conventional cell line experiment models. In addition, the biology of the keloids can easily be assessed to identify predictive markers for responses to treatment regimens that are currently actively under research in various centers.

Background: Nowadays, a number of patients seeking cosmetic surgery for their sunken upper eyelid are increasing. The aim of this study was to provide an overview of the various treatment options for sunken superior sulcus with reported complications and to discuss effective methods for treatment. Methods: In a PubMed search, studies involving patients undergoing correction of sunken superior sulcus with various treatment options were included. Results: A systematic search revealed twelve articles representing 680 cases that satisfied inclusion criteria. All were case series, and no randomized controlled studies were found. Five reported on augmentation of the deformity with surgery, while hyaluronic acid filler was used in four reports. There was a report attempting to correct the deformity by the microautologous fat grafting. The combined surgical approaches including ptosis correction with upper blepharoplasty and appropriate fat grafting were used in two reports. About 7.2% of patients (49/680) experienced complications, with 4.3% requiring re-operation, while no severe complications were observed. Conclusions: By careful identification of the clinical features and proper classification of the types of sunken superior sulcus, the treatment plan can be specified.

Unlabelled: Angiogenesis is the development of new capillaries from existing blood vessels and is a prerequisite for the wound-healing process. Many lines of scientific evidences have shown that complicated roles of small guanosine triphosphatases (GTPases) (ras-related C3 botulinum toxin substrate 1 [Rac1], cell division control protein 42 [Cdc42], and ras homolog gene family, member A [RhoA]) in regulation of signal transduction pathways exist to transmit distinct cellular effects on the modulation of actin cytoskeleton remodeling such as cell cycle progression, cell survival, and cell motility. In addition, these small GTPases activate mitogen-activated protein kinase kinase kinases (MAP3Ks) leading to activated mitogen-activated protein kinase kinases (MAPKK), mitogen-activated protein kinase (MAPK), and various transcription factors such as vascular endothelial growth factor with involvement of MAPK signaling pathways.In this study, the authors hypothesized that botulinum toxin A increases angiogenesis via the expression of small GTPases in vivo and in vitro studies.In vivo experiment, 24 Sprague-Dawley rats were randomly divided into 2 groups: a control group and a botulinum toxin A group. Five days prior to superiorly based transverse rectus abdominis myocutaneous flap elevation, the botulinum toxin A (BoTA) group was pretreated with BoTA, while the control group was pretreated with normal saline. quantitative real-time polymerase chain reaction was performed to evaluate the expression of Rac1, RhoA, and Cdc42.The angiogenic effects of botulinum toxin A on human dermal fibroblasts were measured in vitro experiment. To understand the mechanism of botulinum toxin A on small GTPases production of fibroblasts, Rac1, Cdc42, and RhoA were measured using qRT-PCR.The relative messenger ribonucleic acid expression of Rac1, RhoA, and Cdc42 was significantly higher in the BoTA group than in the control group, in every zone and pedicle muscle, on postoperative days 1, 3, and 5. Levels of these molecules increased significantly in human dermal fibroblasts grown in the presence of BoTA compared with control group over 5 IU.Our in vivo and in vitro studies suggest that administration of BoTA upregulates the expression of RhoA, Rac1, and Cdc42 in a dose-dependent manner. MAPK signaling pathway might be involved in BoTA-induced angiogenesis mechanism. Level of evidence: N/A.