Proliferation Of Scar Fibroblasts Research Articles

Network Pharmacology, Molecular Docking Analysis and Experiment Validations on Molecular Targets and Mechanisms of the Dispel-Scar Ointment in Scar Treatment.

Dispel-Scar Ointment is used in Traditional Chinese Medicine to treat scarred tissue and increasing evidence has shown that DSO has potent therapeutic; however, its exact mechanism remains unexplored. This study explored the molecular mechanisms of action of DSO in scarring using network pharmacology, molecular docking, and experimental validation. Public databases were used to predict the bioactive ingredients and putative targets of DSO against scars. A compounds-targets network was constructed using the Cytoscape software. Enrichment analysis was performed using ClueGo and FunRich to specify the biological functions and associated pathways of hub targets. Molecular docking was used to verify the correlation between the major active components and hub targets, visualised using PyMol 2.3. Experimental validations were conducted to elucidate the influence of DSO on keloid fibroblast cells using the CCK-8, wound-scratch, cell reactive oxygen species, and western blot assays. Results：Network pharmacological analysis of DSO for scar treatment identified 146 ingredients and 1078 gene targets. Major targets included, prostaglandin-endoperoxide synthase 2 matrix metallopeptidases, and nitric oxide synthase 2. ClueGo analysis revealed 29 pathways (p<0.05) and FunRich 345 pathways (p<0.05), mainly toll-like receptor, TGF-β, interleukin-4/13, glypican, and tumour necrosis factor-related apoptosis-inducing ligand pathways. Molecular docking showed MMP2-flavoxanthin, MMP9-luteolin and MMP-9-kaempferol bound best to DSO. DSO could inhibit the proliferation and migration of scar fibroblasts and promote their apoptosis in a concentration-dependent manner. DSO also decreased TGF-β1, -βR2, pSMAD2, pSMAD3, SMAD4, CoL1a1, and MMP2 expression. Network pharmacology, molecular docking, and experimental validation showed DSO's potential in treating scars. It may inhibit scars via the TGF-β1/SMADs/MMPs signalling pathway, providing a basis for DSO's scar treatment application.

The Effects of Massage with Topical Agents (Mepiform Ultra Scar Gel or Scarnos Gel) on Scar Tissue Thickness and Fibroblast Proliferation in Rats

Background: Keloid and hypertrophic scars are prominent scars that are excessively repaired with upregulated synthesis, deposition, and accumulation of collagen. Topical agents are used to reduce inflammation and fibrotic changes via reduced transepithelial water loss. Increased mechanical pressure applied through scar massage can accelerate scar maturation by inducing fibroblast proliferation, which enhances the remodeling of connective tissue matrices and collagen degradation.Methods: This study comparatively analyzed the effectiveness of topical agents applied to post-burn wounds on the dorsal surface of Sprague-Dawley rats through twice-daily massaging. Postoperative histological analysis of the tissues was performed after surgical en bloc removal of the treatment area at 4, 10, and 16 weeks.Results: Histological analyses revealed larger amounts of fibroblasts in Mepiform and Scarnos gel-treated tissue than in Vaseline-treated tissue. Granulation was prevented in scars treated with the topical agents.Conclusion: Mepiform Ultra scar gel and Scarnos gel, accompanied by massaging, may be effective anti-scarring topical agents to alleviate contact burn scars in Sprague-Dawley rats.

SNHG1 functions as a ceRNA in hypertrophic scar fibroblast proliferation and apoptosis through miR-320b/CTNNB1 axis.

Hypertrophic scar (HS) is a fibrotic disease caused by skin injury. Competing endogenous RNA (ceRNA) has been demonstrated to implicate in the regulation of cell malignant phenotypes. This research aims to reveal the effect of catenin beta 1 (CTNNB1) on the functions of hypertrophic scar fibroblasts (HSFBs) and its role in a ceRNA network. RNA expression level was assessed by quantitative reverse transcription polymerase chain reaction (RT-qPCR). The proliferation and apoptosis of HSFB was detected via Cell Counting Kit-8 (CCK-8) assay and flow cytometry analysis. Mechanism experiments included RNA pull down assay, luciferase reporter assay and RNA-binding protein immunoprecipitation (RIP) assay were applied to analyze the upstream molecular mechanism of CTNNB1. CTNNB1 was highly expressed in HSFB. CTNNB1 depletion repressed malignant growth of HSFB. Mechanically, CTNNB1 was targeted by microRNA-320b (miR-320b) in HSFB. Small nucleolar RNA host gene 1 (SNHG1) aced as a ceRNA to upregulate CTNNB1 expression via sponging miR-320b in HSFB. CTNNB1 overexpression could reverse the impact of SNHG1 depletion on the proliferation and apoptosis of HSFB. SNHG1 acts as a ceRNA in modulating HSFB proliferation and apoptosis through miR-320b/CTNNB1 axis. SNHG1 act as a ceRNA to promote HSFB growth by sponging miR-320b to upregulate CTNNB1.

Bilayer microneedles based on Bletilla striata polysaccharide containing asiaticoside effectively promote scarless wound healing

The repair of wounds is essential for overcoming injuries, but the process often leads to scars, and the formation mechanism is unclear. Interestingly, Bletilla striata polysaccharide (BSP) is a procoagulant and has anti-inflammatory properties to promote wound healing, which has great research value for scarless wound healing. Herein, we developed a transdermal drug delivery system of BSP/chitosan (CS) composite bilayer dissolvable microneedles (CS-AS-BSP MNs) containing asiaticoside (AS) based on a centrifugation method with a polydimethylsiloxane mould that fulfilled the requirements of wound healing and achieved a scar-free effect. The drug release results showed that this system improved the solubility of AS and maintained the stable release of the drug for a long time. Further experiments indicated that CS-AS-BSP MNs had a good antibacterial effect and reduced the proliferation of human scar fibroblasts. The wound healing effect of CS-AS-BSP MNs was evaluated in an experimental full-thickness-wound rat model, which demonstrated that the covered wound healed completely without scars within 3 weeks. Furthermore, CS-AS-BSP MNs downregulated TGF-β1 and COL Ⅰ, which are fibrosis-related genes, to inhibit scarring. In brief, this study provides a new strategy for meeting the clinical requirements of effective scarless wound dressings.

Adiponectin ameliorates hypertrophic scar by inhibiting Yes-associated protein transcription through SIRT1-mediated deacetylation of C/EBPβ and histone H3

SummaryThe clinical correlation between adiponectin (APN) signal and hypertrophic scar (HS) remains unclear. Here, we found significantly reduced expression of APN receptors (AdipoR1/2) in HS tissues and derived fibroblasts (HFs), suggesting that HS formation may be associated with APN/AdipoR1/2 decline. RNA sequencing and RT-PCR validation revealed that APN significantly elevated the expression of SIRT1. Both in vitro and in vivo experiments confirmed that SIRT1 plays important role in APN inhibiting the fibrotic phenotype transformation and proliferation of scar fibroblasts and improving skin fibrosis. Mechanistically, SIRT1 inhibited the acetylation of C/EBPβ K39, histone H3K27, and H3K9, resulting in impaired transcription activity of C/EBPβ and compact chromatin conformation, thus preventing C/EBPβ from activating the transcription of YAP. Moreover, we found that YAP was critical for the transcriptional regulation of CTGF, CCND1, and CCNE1 by TEAD4. In conclusion, our study revealed the role of APN in antagonizing HS fibrosis by regulating the SIRT1/C/EBPβ/YAP pathway.

TSG-6 inhibits hypertrophic scar fibroblast proliferation by regulating IRE1α/TRAF2/NF-κB signalling.

TNF-stimulated gene (TSG-6) was reported to suppress hypertrophic scar (HS) formation in a rabbit ear model, and the overexpression of TSG-6 in human HS fibroblasts (HSFs) was found to induce their apoptotic death. The molecular basis for these findings, however, remains to be clarified. HSFs were subjected to TSG-6 treatment. Treatment with TSG-6 significantly suppressed HSF proliferation and induced them to undergo apoptosis. Moreover, TSG-6 exposure led to reductions in collagen I, collagen III, and α-SMA mRNA and protein levels, with a corresponding drop in proliferating cell nuclear antigen (PCNA) expression indicative of impaired proliferative activity. Endoplasmic reticulum (ER) stress was also suppressed in these HSFs as demonstrated by decreases in Bip and p-IRE1α expression, downstream inositol requiring enzyme 1 alpha (IRE1α) -Tumor necrosis factor receptor associated factor 2(TRAF2) pathway signalling was inhibited and treated cells failed to induce NF-κB, TNF-α, IL-1β, and IL-6 expression. Overall, ER stress was found to trigger inflammatory activity in HSFs via the IRE1α-TRAF2 axis, as confirmed with the specific inhibitor of IRE1α STF083010. Additionally, the effects of TSG-6 on apoptosis, collagen I, collagen III, α-SMA, and PCNA of HSFs were reversed by the IRE1α activator thapsigargin (TG). These data suggest that TSG-6 administration can effectively suppress the proliferation of HSFs in part via the inhibition of IRE1α-mediated ER stress-induced inflammation (IRE1α/TRAF2/NF-κB signalling).

Circ_0047339 promotes the activation of fibroblasts and affects the development of urethral stricture by targeting the miR-4691-5p/TSP-1 axis

Urethral stricture is related to scar tissue fibrosis, but its pathogenesis is still unclear. This study aims to explore the regulatory mechanism of circular RNA (circRNA) in the occurrence and development of urethral stricture. CircRNA microarray was employed to analyze circRNA expression profiles between human urethral scar tissue and normal urethral tissue. The results of circRNA microarray showed that there were 296 differentially expressed genes between urethral scar tissue and normal urethral tissue. The enrichment analysis of Kyoto encyclopedia of genes and genomes showed that these circRNAs were significantly correlated with ECM–receptor interaction. The first nine differentially expressed circRNA were selected to predict the circRNA–miRNA network. RT-qPCR results showed that circ_0047339 was upregulated considerably in urethral scar tissue. Urethral scar fibroblasts were isolated from human urethral scar tissue and cultured in vitro. After silencing circ_0047339, the proliferation of urethral scar cells decreased significantly, and the expressions of Collagen I (COL-1) and α-smooth muscle actin (α-SMA) also reduced. As a competing endogenous RNA, circ_0047339 could increase the expression of TSP-1 by competitively binding miR-4691-5p. In addition, miR-4691-5p mimic transfection could inhibit the proliferation of urethral scar fibroblasts and the presentation of thrombospondin-1 (TSP-1), α-SMA and COL-1, while circ_0047339 overexpression eliminated this inhibition. Our results showed that circ_0047339 might promote the growth and fibrosis of urethral scar fibroblasts through miR-4691-5p/TSP-1 axis, thus promoting the development of urethral stricture.

Interleukin-10-Modified Adipose-Derived Mesenchymal Stem Cells Prevent Hypertrophic Scar Formation via Regulating the Biological Characteristics of Fibroblasts and Inflammation.

Hypertrophic scar causes serious functional and cosmetic problem, but no treatment method is known to achieve a satisfactory therapeutic effect. However, mesenchymal stem cells show a possible cure prospect. Here, we investigated the effect of interleukin-10-modified adipose-derived mesenchymal stem cells (IL-10-ADMSC) on the formation of hypertrophic scar. In vitro, IL-10-ADMSC could highly express IL-10 and exhibited stronger inhibition of hypertrophic scar fibroblasts (HSFs) proliferation, migration, and extracellular matrix synthesis (the expression of collagen I, collagen III, FN, and α-SMA protein) than ADMSC. In vivo, we found that IL-10-ADMSC speeded up wound healing time and reduced scar area and scar outstanding height. Same as in vitro, IL-10-ADMSC also exhibited stronger inhibition of extracellular matrix synthesis (the expression of collagen I, collagen III protein) in wound than ADMSC. In addition, we also found that IL-10-ADMSC is also a stronger inhibitory effect on inflammation in wound than ADMSC, and IL-10-ADMSC inhibited TGF-β/Smads and NF-κB pathway. In conclusion, IL-10-ADMSC demonstrated the ability to prevent hypertrophic scar formation. And its possible molecular mechanism might be related to IL-10-ADMSC inhibiting the proliferation and migration of the synthesis of extracellular matrix of HSFs, and IL-10-ADMSC inhibited the inflammation during the wound healing.

Knockdown of lncRNA-NEAT1 expression inhibits hypoxia-induced scar fibroblast proliferation through regulation of the miR-488-3p/COL3A1 axis.

Long non-coding (lnc)RNA nuclear-enriched transcripts 1 (NEAT1) has been demonstrated to be involved in the inhibition of hypoxia-induced scar fibroblast proliferation, but the specific mechanism remains undetermined. The present study found that with the decrease of oxygen concentration, lncRNA NEAT1 was upregulated in hypoxia-induced scar fibroblasts, which promoted the mRNA and protein expression levels of collagen (COL)-I, COL-III and α-smooth muscle actin, thereby suppressing hypoxia-induced scar fibroblasts proliferation. In addition, the microRNA (miR)-488-3p/COL3A1 axis was involved in lncRNA NEAT1's regulation of the proliferation of hypoxia-induced scar fibroblasts. In conclusion, the knockdown of lncRNA-NEAT1 expression can inhibit hypoxia-induced scar fibroblasts proliferation through regulation of the miR-488-3p/COL3A1 axis, which will provide a novel therapeutic target for the treatment of hypertrophic scars.

Local application of triamcinolone acetonide-conjugated chitosan membrane to prevent benign biliary stricture.

Benign biliary stricture (BBS) is the proliferation of fibrous tissue of the biliary tract caused by the biliary operation, bile duct stones, cholangitis, trauma, and other etiologies due to scar contracture. Recent therapeutic strategies to suppress stenosis are insufficient. Here, we developed a sustained-release membrane (SM) of triamcinolone acetonide (TA) with N-succinyl hydroxypropyl chitosan (TASM) for inhibiting fibroblast proliferation in vitro and bile duct hyperplasia in the rabbit model forbenign biliary stricture formation. The TASM were successfully placed in 45 of 50 rabbits. Evaluation of subcutaneous stimulation and acute liver injury confirms the safety of TASM in vivo. Compared to the control group, the TASM can significantly inhibit the proliferation of scar muscle fibroblasts in vitro. ELISA and immunofluorescence showed TASM could increase bFGF level and inhibit expression of TGFβ1 and αSMA. Cholangiographic and histologic examinations demonstrated significantly decreased tissue hyperplasia in the TASM groups compared with the model group. The immunohistochemical staining showed that TASM could reduce the level of cytokine-induced scars and inhibit the proliferation of myofibroblasts. Taken together, the chitosan membrane chemically conjugated with TA can effectively inhibit the benign biliary stricture. Further clinical usage of this membrane may effectively reduce the occurrence of benign biliary stricture.

MicroRNA‑18a‑5p represses scar fibroblast proliferation and extracellular matrix deposition through regulating Smad2 expression

The aim of the present study was to investigate the expression and role of microRNA-18a-5p (miR-18a-5p) during the formation of hypertrophic scar (HS), and to further explore the molecular mechanisms involved. Downregulation of miR-18a-5p in HS tissues and human HS fibroblasts (hHSFs) was detected by reverse transcription-quantitative polymerase chain reaction. The binding sites between miR-18a-5p and the 3'-untranslated region of SMAD family member 2 (Smad2) were predicted by TargetScan and confirmed by dual-luciferase reporter assay. To investigate the role of miR-18a-5p in HS formation, the effects of miR-18a-5p downregulation or upregulation on hHSFs were subsequently determined. Cell proliferation was detected by an MTT assay, while cell apoptosis was measured by flow cytometry. In addition, the protein expression levels of Smad2, Collagen I (Col I) and Col III were examined by western blot assay. The findings indicated that miR-18a-5p downregulation in hHSFs significantly promoted the cell proliferation, decreased cell apoptosis and enhanced the expression levels of Smad2, Col I and Col III protein and mRNA, whereas miR-18a-5p upregulation in hHSFs exerted opposite effects. Notably, the effects of miR-18a-5p upregulation on hHSFs were eliminated by Smad2 upregulation. In conclusion, the data indicated that miR-18a-5p was downregulated during HS formation, and its upregulation repressed scar fibroblast proliferation and extracellular matrix deposition by targeting Smad2. Therefore, miR-18a-5p may serve as a novel therapeutic target for the treatment of HS.

LncRNA TRHDE-AS1 inhibit the scar fibroblasts proliferation via miR-181a-5p/PTEN axis

Hypertrophic scar (HS), a fibroproliferative disorder caused by abnormal wound healing after skin injury, which is characterized by excessive deposition of extracellular matrix and invasive growth of fibroblasts. Recent studies have shown that some non-coding RNA implicated the formation of HS, but the mechanism remains unclear. In this study, we found that lncRNA TRHDE-AS1 was downregulated in HS tissues and HSFs, and the level of lncRNA TRHDE-AS1 negatively correlated with the level of miR-181a-5p in HS tissue and HSFs. Overexpressed lncRNA TRHDE-AS1 significantly suppressed miR-181a-5p level, while promoted HSFs apoptosis and inhibited HSFs proliferation. Further study shown that PTEN was a direct target of miR-181a-5p, and lncRNA TRHDE-AS1 served as a molecular sponge for miR-181a-5p to regulate the expression of PTEN. Overexpression of PTEN could eliminate lncRNA TRHDE-AS1-mediated proliferation suppression of HSFs. In conclusion, our study suggested that lncRNA TRHDE-AS1/miR-181a-5p/PTEN axis plays an important role in promoting hypertrophic scar formation, which may be effectively used as a therapeutic target for hypertrophic scar treatment.

Knockdown of FAM225B inhibits the progression of the hypertrophic scar following glaucoma surgery by inhibiting autophagy.

The formation of a hypertrophic scar (HS) may lead to failure of glaucoma surgery. Long non-coding RNAs (lncRNAs) are involved in the formation of HSs. Moreover, family with sequence similarity 225 member B (FAM225B) is upregulated in HS. However, the role of the lncRNA FAM225B in HS remains unknown. Thus, the present study aimed to investigate the function of FAM225B in HS. Scar fibroblasts were isolated from patients who had undergone glaucoma surgery. Western blotting was used to detect the expressions of Bax, Bcl-2, cleaved caspase 3, p62, ATG7 and Beclin 1, and reverse transcription-quantitative PCR (RT-qPCR) were conducted to determine the level of FAM225B in scar fibroblasts. Microtubule associated protein 1 light chain 3 α staining was performed to examine autophagosomes in scar fibroblasts. Furthermore, cell proliferation was evaluated via 5-ethynyl-2′-deoxyuridine staining. Flow cytometry was conducted to determine cell apoptosis and the levels of reactive oxygen species (ROS) in scar fibroblasts. The cell migratory ability was assessed using a Transwell assay. The results demonstrated that FAM225B knockdown significantly attenuated scar fibroblast proliferation and induced apoptosis. Additionally, transfection of scar fibroblasts with FAM225B small interfering RNA (siRNA) significantly increased the ROS levels and significantly decreased the migration of scar fibroblasts. The FAM225B overexpression-induced increase of scar fibroblast proliferation and migration was significantly reversed by 3-methyladenine administration. The results suggested that knockdown of FAM225B significantly inhibited the proliferation of scar fibroblasts by inhibiting autophagy. Therefore, knockdown of FAM225B could inhibit scar fibroblast proliferation after glaucoma surgery by inhibiting autophagy. These findings may provide a novel perspective of developing treatment strategy for the patients with HSs after glaucoma surgery.

The Inhibition of Cell Proliferation of Bile Duct Scar Fibroblasts in Miniature Pigs by 5-fluorouracil and its Mechanism

The Inhibition of Cell Proliferation of Bile Duct Scar Fibroblasts in Miniature Pigs by 5-fluorouracil and its Mechanism

Tetramethylpyrazine Induces Apoptosis and Inhibits Proliferation of Hypertrophic Scar-Derived Fibroblasts via Inhibiting the Phosphorylation of AKT.

Hypertrophic scar (HS) is a serious fibrotic skin disease and often considered as a kind of benign skin tumor. Tetramethylpyrazine (TMP), the main chemical composition of the traditional Chinese medicine Chuanxiong Rhizoma, has shown significant clinical benefits in the treatment of fibrosis disease and tumor, while the role in HS and the concrete mechanisms remain elusive. Herein, the protective effects of TMP in the treatment of HS was investigated and the results showed that the protein expression levels of type I collagen (Col I), type III collagen (Col III), and α-smooth muscle actin (α-SMA) were all inhibited remarkably after addition of TMP in HS-derived fibroblasts (HFs). Moreover, TMP also suppressed fibroblast proliferative and induced cell apoptosis. The protein expression levels of Caspase-3 and Bcl-2 were all decreased comparing with the control group while proapoptotic proteins Bax and Cleaved Caspase-3 were increased. In addition, TMP treatment markedly reduced the phosphorylation levels of AKT. Taken together, our investigations demonstrated that TMP could down-regulate the expression of fibrosis-related molecules, inhibit scar fibroblast proliferation and activate cell apoptosis, during which AKT pathway was involved. Thus, this study shed more light on the pharmacological mechanisms of TMP, and provided a novel therapeutic alternative for prevention and treatment of HS.

Inhibition of glutaminase to reverse fibrosis in iatrogenic laryngotracheal stenosis.

Glutamine metabolism is a critical energy source for iatrogenic laryngotracheal stenosis (iLTS) scar fibroblasts, and glutaminase (GLS) is an essential enzyme converting glutamine to glutamate. We hypothesize that the GLS-specific inhibitor BPTES will block glutaminolysis and reduce iLTS scar fibroblast proliferation, collagen deposition, and fibroblast metabolism in vitro. Test-tube Lab Research. Immunohistochemistry of a cricotracheal resection (n = 1) and a normal airway specimen (n = 1) were assessed for GLS expression. GLS expression was assessed in brush biopsies of subglottic/tracheal fibrosis and normal airway from patients with iLTS (n = 6). Fibroblasts were isolated and cultured from biopsies of subglottic/tracheal fibrosis (n = 6). Fibroblast were treated with BPTES and BPTES + dimethyl α-ketoglutarate (DMK), an analogue of the downstream product of GLS. Fibroblast proliferation, gene expression, protein production, and metabolism were assessed in all treatment conditions and compared to control. GLS was overexpressed in brush biopsies of iLTS scar specimens (P = .029) compared to normal controls. In vitro, BPTES inhibited iLTS scar fibroblast proliferation (P = .007), collagen I (Col I) (P < .0001), collagen III (P = .004), and α-smooth muscle actin (P = .0025) gene expression and protein production (P = .031). Metabolic analysis demonstrated that BPTES reduced glycolytic reserve (P = .007) but had no effects on mitochondrial oxidative phosphorylation. DMK rescued BPTES inhibition of Col I gene expression (P = .0018) and protein production (P = .021). GLS is overexpressed in iLTS scar. Blockage of GLS with BPTES significantly inhibits iLTS scar fibroblasts proliferation and function, demonstrating a critical role for GLS in iLTS. Targeting GLS to inhibit glutaminolysis may be a successful strategy to reverse scar formation in the airway. NA Laryngoscope, 2020.

Effects of usnic acid on the proliferation and migration activity of human umbilical vein endothelial cells and hypertrophic scar fibroblasts

Objective To Explore the effect of usnic acid on the proliferation and migration of human umbilical vein endothelial cells (HUVECs) and human hypertrophic scar fibroblasts (HSFBs) . Methods HSFBs were isolated and cultured in vitro, and their morphological features were analyzed. Different concentrations of usnic acid (0, 5, 10, 20, 50 μmol/L) were added to the HUVECs and HSFBs, control group was treated with Dimethyl sulfoxide (DMSO), after culture for 48 h, the proliferation activity of cells was detected with the MTS kit. The migration ability of two cells was analyzed by wound healing assay. The experimental data were analyzed by SPSS19.0 software, with P<0.05 as the statistical significance. Results Compared with the control group (100%), 5, 10, 20, 50 μmol/L usnic acid could significantly inhibit the proliferation of HUVECs, and the cell viability was reduced to (91.67±10.99)%, t=0.068, P>0.05; (40.68±8.87)%, t=5.280, P<0.01; (33.97±2.12)%, t=1.140, P<0.01; (20.39±0.84)%, t=8.280, P<0.01. respectively. Under the same experimental conditions, 20 μmol/L and 50 μmol/L usnic acid could inhibit the proliferation of HSFBs, cell viability was (76.16±11.03)% and (51.59±6.82)% respectively. 1, 5, 10 μmol/L usnic acid had no inhibitory effect on HSFBs cell proliferation. The migration of HUVECs was inhibited by 1, 10, 20 μmol/L of usnic acid (81.26±10.82, t=0.000, P<0.01; 71.81±3.96, t=3.780, P<0.01; 54.91±8.47, t=5.280, P<0.01). Meanwhile, usnic acid has no inhibition effect on HSFBs migration. Conclusion Usnic acid had the ability to inhibit HUVECs and HSFBs proliferation, and the ability to inhibit HUVECs migration. Key words: Usnic acid; Human umbilical vein endothelial cells; Human hypertrophic scar fibroblasts; Cell proliferation; Cell migration

Botulinum toxin type A suppresses pro-fibrotic effects via the JNK signaling pathway in hypertrophic scar fibroblasts.

Hypertrophic scar is a dermal fibroproliferative disease characterized by the overproduction and deposition of extracellular matrix, and the hyperproliferation and enhanced angiogenesis of fibroblasts, along with their enhanced differentiation to myofibroblasts. Botulinum toxin type A shows potential for prevention of hypertrophic scar formation; however, its effectiveness in attenuating skin fibrosis and the related mechanism are unclear. In this study, human scar fibroblasts were cultured and stimulated with botulinum toxin type A, and the changes in fibroblast proliferation, migration, and protein expression of pro-fibrotic factors were evaluated with colorimetric, scratch, and enzyme-linked immunosorbent assays and western blotting, respectively. Botulinum toxin type A treatment decreased the proliferation and migration of human scar fibroblasts compared with those of untreated controls. Protein expression levels of pro-fibrotic factors (transforming growth factor β1, interleukin-6, and connective tissue growth factor) were also inhibited by botulinum toxin type A, whereas the JNK phosphorylation level was increased. Activation of the JNK pathway demonstrated the inhibitory effects of the toxin on human scar fibroblast proliferation and production of pro-fibrotic factors, suggesting that the suppressive effects of botulinum toxin type A are closely associated with JNK phosphorylation. Overall, this study showed that botulinum toxin type A has a suppressive effect on extracellular matrix production and scar-related factors in human scar fibroblasts in vitro, and that regulation of JNK signaling plays an important role in this process. Our results provide a theoretical basis, at the cellular level, for the therapeutic use of botulinum toxin type A.

Endogenous peptide LYENRL prevents the activation of hypertrophic scar-derived fibroblasts by inhibiting the TGF-β1/Smad pathway

Hypertrophic scar formation is a fibroproliferative disorder caused by abnormal wound healing. At present, there are limited treatment strategies for hypertrophic scars. In this study, we identified an endogenous peptide, LYENRL, through peptidomics screening that is downregulated in scar skin tissues. The peptide exhibited concentration dependent inhibitory effects on the proliferation, migration and extracellular matrix (ECM) production of scar fibroblasts. By eukaryotic transcriptome sequencing analysis, we noted that LYENRL downregulated gene sets in scar fibroblasts were associated with the transforming growth factor-β (TGF-β) signaling pathway. Further experiments revealed that LYENRL was able to inhibit the activation of TGF-β1/Smad signaling and TGF-β1-induced activation of scar fibroblasts at the source by blocking the binding of AP-1 to the corresponding region of the Tgfb1 promoter, which in turn inhibited gene expression of Tgfb1. Taken together, we concluded that the effects of LYENRL on scar fibroblasts make it a potential peptide drug for hypertrophic scar treatment.

Cuprous oxide nanoparticles reduces hypertrophic scarring by inducing fibroblast apoptosis.

BackgroundLess apoptosis and excessive growth of fibroblasts contribute to the progression of hypertrophic scar formation. Cuprous oxide nanoparticles (CONPs) could have not only inhibited tumor by inducing apoptosis and inhibiting proliferation of tumor cells, but also promoted wound healing. The objective of this study was to further explore the therapeutic effects of CONPs on hypertrophic scar formation in vivo and in vitro.MethodsIn vivo, a rabbit ear scar model was established on New Zealand albino rabbits. Six full-thickness and circular wounds (10 mm diameter) were made to each ear. Following complete re-epithelization observed on postoperative day 14, an intralesional injection of CONPs or 5% glucose solution was conducted to the wounds. The photo and ultrasonography of each wound were taken every week and scars were harvested on day 35 for further histomorphometric analysis. In vitro, the role of CONPs in human hypertrophic scar fibroblasts (HSFs) apoptosis and proliferation were evaluated by Tunnel assay, Annexin V/PI staining, cell cycle analysis, and EdU proliferation assay. The endocytosis of CONPs by fibroblasts were detected through transmission electron microscopy (TEM) and the mitochondrial membrane potential and ROS production were also detected.ResultsIn vivo, intralesional injections of CONPs could significantly improve the scar appearance and collagen arrangement, and decreased scar elevation index (SEI). In vitro, CONPs could prominently inhibit proliferation and induce apoptosis in HSFs in a concentration-dependent manner. In addition, CONPs could be endocytosed into mitochondria，damage the mitochondrial membrane potential and increase ROS production.ConclusionCONPs possessed the therapeutic potential in the treatment of hypertrophic scar by inhibiting HSFs proliferation and inducing HSFs apoptosis.