Downregulation of Epac Reduces Fibrosis and Induces Apoptosis Through Akt Signaling in Human Keloid Fibroblasts.

BACKGROUND: A keloid is a type of pathological scar often caused by abnormal tissue repair after a skin injury and is more common in genetically susceptible individuals. cAMP is a universal second messenger and regulates critical physiological processes, including calcium homeostasis, secretion, cell fate, and gene transcription, by affecting the expression of the exchange protein directly activated by cAMP (Epac). Epac has two isoforms, Epac1 (cAMP-GEF-1) and Epac2 (cAMP-GEF-II), which show varying expression levels depending on the tissue and cell type. The expression of Epac1 in keloids has not yet been investigated. MATERIALS AND METHODS: Keloid tissue and normal dermal skin tissue were analyzed by hematoxylin and eosin staining and immunofluorescence. Primary human keloid fibroblasts (HKFs) and human normal dermal fibroblasts were studied using immunofluorescence, wound healing tests, reverse transcription polymerase chain reaction, and western blot analysis with different concentrations of the Epac1 inhibitor ESI-09. RESULTS: Downregulation of Epac was performed using ESI-09, a specific Epac inhibitor. The proliferation and migration capacities of HKFs and human normal dermal fibroblasts showed an ESI-09 concentration-dependent decrease. Furthermore, the apoptosis rates were significantly different between fibroblasts treated with ESI-09 and control fibroblasts. In addition, the phosphorylation level of Akt was significantly decreased, indicating that ESI-09 reduces fibrosis and induces apoptosis through Akt signaling in HKFs. CONCLUSIONS: Our results illustrate the role of Epac1 in regulating fibroblast function during keloid pathogenesis and indicate that Epac1 may be a potential therapeutic target in keloid treatment.

LncRNA XIST promotes extracellular matrix synthesis, proliferation and migration by targeting miR-29b-3p/COL1A1 in human skin fibroblasts after thermal injury.

BACKGROUND: Long noncoding RNAs (lncRNAs) have been reported to be associated with dermis process during burn wound healing. This study aimed to investigate the role of lncRNA X-inactive specific transcript (XIST) in human skin fibroblasts (HSF) and extracellular matrix (ECM) as well as the regulatory network of XIST/microRNA-29b-3p (miR-29b-3p)/collagen 1 alpha 1 (COL1A1). METHODS: The wound samples were collected from 25 patients with deep partial thickness burn at day 5 after burn. The thermal injured model was established using HSF cells. The expressions of XIST, miR-29b-3p and COL1A1 were measured by quantitative real-time polymerase chain reaction and western blot. ECM synthesis, cell proliferation and migration were detected by western blot, cell counting kit-8 and trans-well assays, respectively. The interaction between miR-29b-3p and XIST or COL1A1 was explored by bioinformatics analysis and luciferase reporter assay. RESULTS: The expressions of XIST and COL1A1 were enhanced but miR-29b-3p expression was decreased after thermal injury. XIST overexpression promoted ECM synthesis, cell proliferation and migration in thermal injured HSF cells. However, XIST knockdown played an opposite effect. miR-29b-3p overexpression inhibited ECM synthesis, cell proliferation and migration, which was reversed by XIST. COL1A1 silence suppressed ECM synthesis, cell proliferation and migration by miR-29b-3p targeting. Moreover, COL1A1 up-regulation weakened the effect of XIST silence on ECM synthesis and HSF cell function. CONCLUSION: XIST promoted ECM synthesis, cell proliferation and migration by sponging miR-29b-3p and targeting COL1A1 in HSF cells after thermal injury, indicating the promoting role of XIST in wound healing.

LncRNA XIST promotes extracellular matrix synthesis, proliferation and migration by targeting miR-29b-3p/COL1A1 in human skin fibroblasts after thermal injury

Background: Long noncoding RNAs (lncRNAs) have been reported to be associated with dermis process during burn wound healing. This study aimed to investigate the role of lncRNA X-inactive specific transcript (XIST) in human skin fibroblasts (HSF) and extracellular matrix (ECM) as well as the regulatory network of XIST/microRNA-29b-3p (miR-29b-3p)/collagen 1 alpha 1 (COL1A1). Methods: The wound samples were collected from 25 patients with deep partial thickness burn at day 5 after burn. The thermal injured model was established using HSF cells. The expressions of XIST, miR-29b-3p and COL1A1 were measured by quantitative real-time polymerase chain reaction and western blot. ECM synthesis, cell proliferation and migration were detected by western blot, cell counting kit-8 and trans-well assays, respectively. The interaction between miR-29b-3p and XIST or COL1A1 was explored by bioinformatics analysis and luciferase reporter assay. Results: The expressions of XIST and COL1A1 were enhanced but miR-29b-3p expression was decreased after thermal injury. XIST overexpression promoted ECM synthesis, cell proliferation and migration in thermal injured HSF cells. However, XIST knockdown played an opposite effect. miR-29b-3p overexpression inhibited ECM synthesis, cell proliferation and migration, which was reversed by XIST. COL1A1 silence suppressed ECM synthesis, cell proliferation and migration by miR-29b-3p targeting. Moreover, COL1A1 up-regulation weakened the effect of XIST silence on ECM synthesis and HSF cell function. Conclusion: XIST promoted ECM synthesis, cell proliferation and migration by sponging miR-29b-3p and targeting COL1A1 in HSF cells after thermal injury, indicating the promoting role of XIST in wound healing.

E2F1 Hinders Skin Wound Healing by Repressing Vascular Endothelial Growth Factor (VEGF) Expression, Neovascularization, and Macrophage Recruitment.

BACKGROUND: Refractory surface of wound and dermal chronic ulcer are largely attributed to poor neovascularization. We have previously shown that E2F1 suppresses VEGF expression in the ischemic heart, and that genetic deletion of E2F1 leads to better cardiac recovery. However, whether E2F1 has a role in dermal wound healing is currently not known. METHODS AND RESULTS: Skin wounds were surgically induced in E2F1-null (E2F1-/-) mice and WT littermates. E2F1-/- displayed an accelerated wound healing including wound closure, dermal thickening and collagen deposition, which was associated with an increased endothelial cell proliferation and greater vessel density in the border zone of the wound. Furthermore, more macrophages were recruited to the skin lesions and the level of VEGF expression was markedly higher in E2F1-/- than in WT mice. CONCLUSIONS: E2F1 hinders skin wound healing by suppressing VEGF expression, neovascularization, and macrophage recruitment. Strategies that target E2F1 may enhance wound healing.

Lateral crus graft with autologous rib cartilage for cleft lip nostril asymmetry: a report of 35 cases.

A surgical technique of lateral crus strut graft to correct the deformity of nostril contour and improve asymmetric nostril shape by autologous rib cartilage was reported. Thirty-five patients (20 males and 15 females), with a mean age of 19 years (range of 16-26 years) were included in this study. All of the patients suffered moderate to severe unilateral cleft lip nostril deformity and underwent surgical technique of lateral crus strut graft by autologous rib cartilage to correct the asymmetric nostril contour from 2010 to 2012. The views of the nostril contour on both sides were reviewed and some parameters were measured at different time points (preoperatively, and 3 months and one year postoperatively) including the long axis and short axis of the nostrils. The differences in nostrils including long axis, short axis, elliptical area and eccentricity on the both sides were compared at different time points. The differences in the long axis and eccentricity of the nostrils on the two sides were decreased significantly between the preoperative view and postoperative view (P<0.05). The surgical technique of lateral crus graft with autologous rib cartilage is effective to correct the abnormal nostril contour and improve the asymmetry for unilateral cleft clip patients.