Fibroblast Cell Migration Research Articles

The Role of Epigallocatechin-3-gallate (EGCG) In Inhibiting MMP3 Expression and Human Pterygium Fibroblast Migration: A Review

Background: Pterygium is characterized by the overgrowth of fibroblasts and the remodeling of the extracellular matrix (ECM), driven by MMPs. The review outlines the pathophysiology of pterygium, emphasizing the role of MMP-3 in cell motility, proteolysis, and angiogenesis. The recurrence rate of pterygium following surgical excision remains a significant challenge, with current adjuvant therapies like mitomycin-C presenting serious side effects. Methods: The review synthesizes findings from various studies on the effects of EGCG on MMP-3 expression and fibroblast migration. It discusses the mechanisms by which EGCG inhibits MMP-3 activity and its potential impact on pterygium progression. Findings: EGCG has been shown to inhibit MMP-3 expression and activity in several models, including mouse Lewis lung carcinoma-derived cells and photoaged hairless mouse models. It also suppresses the migration of human pterygium fibroblast cells, potentially preventing pterygium formation. EGCG's ability to reduce oxidative stress and modulate inflammatory pathways further supports its therapeutic potential. Conclusion: EGCG emerges as a promising agent for inhibiting MMP-3 expression and human pterygium fibroblast migration, offering a safer alternative to current adjuvant therapies. Its anti-inflammatory, antioxidant, and anti-angiogenic properties make it a potential therapeutic option for managing pterygium, warranting further clinical investigation.

FOXO3A Plays a Role in Wound Healing by Regulating Fibroblast Mitochondrial Dynamics

The skin plays a protective role against harmful environmental stress such as UV rays. Therefore, the skin is constantly exposed to potential injuries, and wound healing is a vital process for the survival of all higher organisms. Wound healing is dependent on aging and metabolic status at a whole-body level. Because the FOXO family plays a role in aging and metabolism, we investigated the molecular functions of FOXO3A in skin wound healing using FoxO3a-/- mice. We observed that FoxO3a-/- mice showed accelerated skin wound healing. During wound healing, more fibroblasts accumulated at the wound edges and migrated into the wound bed in FoxO3a-/- mice. Moreover, cell migration of dermal fibroblasts isolated from FoxO3a-/- mice was significantly induced. During the invitro cell migration, we observed accelerated mitochondrial fragmentation and decreased oxygen consumption in the mitochondria of FoxO3a-/- fibroblasts. These changes were caused by the upregulation of mitochondrial Rho GTPase 1, which is an essential mediator of microtubule-based mitochondrial motility. Mitochondrial Rho GTPase 1 inhibition significantly attenuated cell migration, mitochondrial fragmentation, and mitochondrial recruitment to the leading edge of the cells. These data indicate that FOXO3A plays a crucial role in wound healing by regulating mitochondrial dynamics.

Histone Deacetylase 7-Derived 7-Amino Acid Peptide Increases Skin Wound Healing via Regulating Epidermal Fibroblast Proliferation and Migration.

Due to the complexity of wound healing, how to achieve successful healing is a significant clinical challenge. In this study, we found that the histone deacetylase-7-derived 7-amino acid peptide (7A, MHSPGAD), especially its phosphorylated version 7Ap (MH[pSer]PGAD), increased dermal fibroblast cell HDFα proliferation and migration via elevated delta-catenin (CTNND1) serine phosphorylation-mediated beta-catenin (CTNNB) nuclear translocation and subsequent upregulation of c-Myc and cyclin D1 expression. 7Ap physically interacted with platelet-derived growth factor receptor (PDGFR) and increased PDGFR interaction with cyclin-dependent kinase 6 (CDK6). The PDGFR siRNA or CDK6 siRNA knockdown ablated 7AP-induced CTNND1 phosphorylation and subsequent c-Myc/cyclin D1 expression, indicating a novel 7Ap-PDGFR-CDK6-CTNND1/CTNNB signal pathway in regulating fibroblast proliferation and migration. Furthermore, 7Ap increased human umbilic vein endothelial cell proliferation and tube formation, suggesting an angiogenic effect. In a full-thickness excision wound rat model, the local administration of 50 ng/mL of 7Ap in hydrogel exerted a similar effect as 1 μg/mL vascular endothelial growth factor on accelerating wound healing, featured by enhanced fibroblast proliferation and migration, collagen deposition, and increased new vessel formation during the early phase of wound healing. Taken together, this study not only elicited a novel signal pathway in fibroblast proliferation but also paved an avenue to develop 7Ap as a treatment option for skin wound healing.

The Effect of Platelet Fibrin Plasma (PFP) on Postoperative Refractory Wounds: Physiologically Concentrated Platelet Plasma in Wound Repair.

Surgical wounds that can't complete primary healing three weeks after surgery are called postoperative refractory wounds. Postoperative refractory wounds would bring great physical and life burdens to the patients and seriously affect their quality of life. To investigate the effect of platelet fibrin plasma (PFP) on postoperative refractory wound healing. The composition of PFP was analyzed using blood routine and blood biochemicals. Clinical data were collected that met the inclusion criteria after treatment with PFP, and the efficacy of PFP was evaluated by wound healing rate and days to healing. Next, growth factor content in PFP, PRP, and PPP was analyzed using ELISA, and PFP-treated cells were applied to investigate the effect of PFP on fibroblast and endothelial cell function. PFP component analysis revealed no statistical difference between platelet concentration in PFP and physiological concentration. Clinical statistics showed that PFP treatment was effective in the postoperative refractory wound (four-week wound healing rate > 90%), significantly better than continuous wound dressing. Meanwhile, our result also proved that PFP treatment significantly enhanced vascularization by upregulated the expression level of CD31 and improved granulation tissue thickness. Activated PFP, PRP, and PPP could continuously release growth factors in vitro and the amount of growth factors released by PRP and PFP was significantly higher than PPP. In vitro studies demonstrated that active PFP could improve cell proliferation, migration, adhesion, and angiogenesis in fibroblasts and endothelial cells. Physiologically concentrated platelet plasma promoted wound healing and improved related cellular functions. The modified PFP (responsible for accelerating wound healing and enhancing the migration and proliferation of fibroblasts and endothelial cells) was prepared and analyzed for its clinical effectiveness in postoperative refractory wounds. Physiologically concentrated platelet plasma promoted wound healing and improved related cellular functions. The preparation of PFP could significantly reduce the amount of prepared blood, with a good application value for postoperative wounds. PFP can be considered a treatment option, especially for postoperative refractory wounds.

3D Printing of Biocompatible and Antibacterial Silica-Silk-Chitosan-Based Hybrid Aerogel Scaffolds Loaded with Propolis.

The aim of this study is to design a therapeutic enhanced three-dimensional (3D) silk fibroin (SF)-based scaffold containing propolis (Ps)-loaded chitosan (CH) nanocarriers. To this aim, we initially synthesized a hybrid gel-based ink by a synergistic sol-gel and self-assembly approach and then processed the resulting gels by microextrusion-based 3D printing followed by supercritical drying to obtain 3D hybrid aerogel scaffolds. Ps was utilized to enhance the final scaffold's bactericidal efficacy and cell responsiveness. For the synthesis of the scaffold, two Ps loading methods (in preprint and postprinting steps) were investigated in order to optimize the Ps drug quantities in the scaffold and maximize the antibacterial properties of scaffold. In the postprinting Ps loading step, the hybrid silica-oxidized SF (SFO)-CH hydrogel ink was 3D printed into a construct with an interconnected porous structure, and then, Ps was loaded into the printed construct. In the preprint loading method, PS was incorporated into the SF and a hydrolyzed silane solution prior to gelation. The morphological studies demonstrate that the addition of Ps encapsulated CH nanoparticles (NPs) into the hydrogel solution improved the porosity of the developed scaffolds. The rheological analysis of the designed gel ink with and without Ps loading and the release kinetics were studied. The antimicrobial results show that the Ps-loaded scaffolds in the postprinting step exhibited superior antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) strains compared to a preprinted Ps-loaded scaffold. Direct and indirect in vitro cytotoxicity tests also confirmed the designed Ps-loaded scaffold biocompatibility toward a mouse fibroblast (L929) cell line. We demonstrated that the scaffold formulated by propolis-loaded chitosan NPs can enhance the migration and proliferation of L929 fibroblast cells. The obtained results prove the promise of the designed 3D printed silica-SFO-CH-Ps scaffolds as a potent 3D scaffold to mediate tissue regeneration but also as an antibacterial highly porous matrix to support wound healing.

PTGES is involved in myofibroblast differentiation via HIF-1α-dependent glycolysis pathway.

Lung cancer is the leading cause of cancer-related deaths worldwide. Patients with lung cancer usually exhibit poor prognoses and low 5-year survival rates. Idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) are both chronic lung dysfunctions resulting in lung fibrosis and increased risk of lung cancer. Myofibroblasts contribute to the progression of asthma, COPD and IPF, leading to fibrosis in the airway and lungs. A growing body of evidence demonstrates that metabolic reprogramming is a major hallmark of fibrosis, being important in the progression of fibrosis. Using gene expression microarray, we identified and validated that the lipid metabolic pathway was upregulated in lung fibroblasts upon interleukin (IL)-4, IL-13 and tumour necrosis factor (TNF)-α treatment. In this study, we described that prostaglandin E synthase (PTGES) was upregulated in lung fibroblasts after IL-4, IL-13 and TNF-α treatments. PTGES increased α-SMA levels and promoted lung fibroblast cell migration and invasion abilities. Furthermore, PTGES was upregulated in a lung fibrosis rat model invivo. PTGES increased AKT phosphorylation, leading to activation of the HIF-1α-glycolysis pathway in lung fibroblast cells. HIF-1α inhibitor or 2-DG treatments reduced α-SMA expression in recombinant PTGES (rPTGES)-treated lung fibroblast cells. Targeting PGE2 signalling in PTGES-overexpressing cells by a PTGES inhibitor reduced α-SMA expression. In conclusion, the results of this study demonstrate that PTGES increases the expression of myofibroblast marker via HIF-1α-dependent glycolysis and contributes to myofibroblast differentiation.

MSC Exosomes Containing Valproic Acid Promote Wound Healing by Modulating Inflammation and Angiogenesis.

Chronic wounds that are difficult to heal pose a major challenge for clinicians and researchers. Currently, common treatment methods focus on isolating the wound from the outside world, relying on the tissue at the wound site to grow and heal unaided. Umbilical cord mesenchymal stem cell (MSC) exosomes can promote wound healing by enhancing new blood vessel growth at the wound site. Valproic acid (VPA) reduces the inflammatory response and acts on macrophages to accelerate wound closure. In this study, VPA was loaded into umbilical cord MSC exosomes to form a drug carrier exosome (VPA-EXO) with the aim of investigating the effect of VPA-EXO on wound healing. This study first isolated and obtained umbilical cord MSC exosomes, then added VPA to the exosomes and explored the ability of VPA-EXO to promote the proliferation and migration of human skin fibroblasts (HSFs) and human umbilical vein endothelial cells (HUVECs), as well as the ability to promote the angiogenesis of HUVECs, by using scratch, Transwell, and angiogenesis assays. An in vitro cell model was established and treated with VPA-EXO, and the expression levels of inflammation and pro-angiogenesis-related proteins and genes were examined using Western blot and qRT-PCR. The therapeutic effect of VPA-EXO on promoting wound healing in a whole skin wound model was investigated using image analysis of the wound site, H&E staining, and immunohistochemical staining experiments in a mouse wound model. The in vitro model showed that VPA-EXO effectively promoted the proliferation and migration of human skin fibroblast cells and human umbilical vein endothelial cells; significantly inhibited the expression of MMP-9, IL-1β, IL-8, TNF-α, and PG-E2; and promoted the expression of vascular endothelial growth factors. In the mouse wound model, VPA-EXO reduced inflammation at the wound site, accelerated wound healing, and significantly increased the collagen content of tissue at the wound site. As a complex with dual efficacy in simultaneously promoting tissue regeneration and inhibiting inflammation, VPA-EXO has potential applications in tissue wound healing and vascular regeneration. In future studies, we will further investigate the mechanism of action and application scenarios of drug-loaded exosome complexes in different types of wound healing and vascular regeneration.

Fabrication of MIL-101(Fe)-embedded biopolymeric films and their biomedical applications

AbstractThe development of wound-dressing materials with superior therapeutic effects, controlled bioactive agent release, and optimal mechanical properties is crucial in healthcare. This study introduces innovative hydrogel films designed for the sustained release of the local anesthetic drug Procaine (PC), triggered by pH changes. These films are composed of MIL-101(Fe) particles and pectin polymers. MIL-101(Fe) was chosen for its high surface area, stability in aqueous environments, and biocompatibility, ensuring low toxicity to normal cells. MIL-101(Fe)-embedded-pectin hydrogels were synthesized and characterized using Fourier-transformed infrared (FTIR) spectroscopy, thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD), inductively coupled plasma (ICP) spectrometry, particle size analysis, and goniometry. Rheological analysis assessed the hydrogels’ viscoelastic behavior, and UV-spectrophotometry was utilized for drug loading and release studies. The hydrogels exhibited shear-thinning properties, enhancing shape adaptability and recovery, crucial for wound-dressing applications. Controlled drug release was achieved by maintaining the PC solution’s pH between 8.2 and 9.8 during the drug-loading step. The hydrogel film’s impact on wound healing was evaluated through an in vitro wound healing assay, and cytotoxicity was assessed using a WST-1 cell proliferation assay with human dermal fibroblast cells. Results demonstrated that pectin composites enhance cell viability and support fibroblast cell migration without adverse effects, indicating their potential for effective wound healing applications. This study highlights the potential of MIL-101(Fe)-embedded-pectin hydrogels in advancing wound care technology. Graphical Abstract MIL-101(Fe)-embedded pectin film as wound dressing

SIRT3 sulfhydration using hydrogen sulfide inhibited angiotensin II-induced atrial fibrosis and vulnerability to atrial fibrillation via suppression of the TGF-β1/smad2/3 signalling pathway

Atrial fibrosis is associated with the occurrence of atrial fibrillation (AF) and regulated by the transforming growth factor-β1 (TGF-β1)/Smad2/3 signalling pathway. Unfortunately, the mechanisms of regulation of TGF-β1/Smad2/3-induced atrial fibrosis and vulnerability to AF remain still unknown. Previous studies have shown that sirtuin3 (SIRT3) sulfhydration has strong anti-fibrotic effects. We hypothesised that SIRT3 sulfhydration inhibits angiotensin II (Ang-II)-induced atrial fibrosis via blocking the TGF-β1/Smad2/3 signalling pathway. In this study, we found that SIRT3 expression was decreased in the left atrium of patients with AF compared to that in those with sinus rhythm (SR). In vitro, SIRT3 knockdown by small interfering RNA significantly expanded Ang-II-induced atrial fibrosis and TGF-β1/Smad2/3 signalling pathway activation, whereas supplementation with Sodium Hydrosulfide (NaHS, exogenous hydrogen sulfide donor and sulfhydration agonist) and SIRT3 overexpression using adenovirus ameliorated Ang-II-induced atrial fibrosis. Moreover, we observed suppression of the TGF-β1/Smad2/3 pathway when Ang-II was combined with NaHS treatment, and the effect of this co-treatment was consistent with that of Ang-II combined with LY3200882 (Smad pathway inhibitor) on reducing atrial fibroblast proliferation and cell migration in vitro. Supplementation with dithiothreitol (DTT, a sulfhydration inhibitor) and adenovirus SIRT3 shRNA blocked the ameliorating effect of NaHS and AngII co-treatment on atrial fibrosis in vitro. Finally, continued treatment with NaHS in rats ameliorated atrial fibrosis and remodelling, and further improved AF vulnerability induced by Ang-II, which was reversed by DTT and adenovirus SIRT3 shRNA, suggesting that SIRT3 sulfhydration might be a potential therapeutic target in atrial fibrosis and AF.

GelMA loaded with platelet lysate promotes skin regeneration and angiogenesis in pressure ulcers by activating STAT3

Pressure ulcers (PU) are caused by persistent long-term pressure, which compromises the integrity of the epidermis, dermis, and subcutaneous adipose tissue layer by layer, making it difficult to heal. Platelet products such as platelet lysate (PL) can promote tissue regeneration by secreting numerous growth factors based on clinical studies on skin wound healing. However, the components of PL are difficult to retain in wounds. Gelatin methacrylate (GelMA) is a photopolymerizable hydrogel that has lately emerged as a promising material for tissue engineering and regenerative medicine. The PL liquid was extracted, flow cytometrically detected for CD41a markers, and evenly dispersed in the GelMA hydrogel to produce a surplus growth factor hydrogel system (PL@GM). The microstructure of the hydrogel system was observed under a scanning electron microscope, and its sustained release efficiency and biological safety were tested in vitro. Cell viability and migration of human dermal fibroblasts, and tube formation assays of human umbilical vein endothelial cells were applied to evaluate the ability of PL to promote wound healing and regeneration in vitro. Real-time polymerase chain reaction (PCR) and western blot analyses were performed to elucidate the skin regeneration mechanism of PL. We verified PL’s therapeutic effectiveness and histological analysis on the PU model. PL promoted cell viability, migration, wound healing and angiogenesis in vitro. Real-time PCR and western blot indicated PL suppressed inflammation and promoted collagen I synthesis by activating STAT3. PL@GM hydrogel system demonstrated optimal biocompatibility and favorable effects on essential cells for wound healing. PL@GM also significantly stimulated PU healing, skin regeneration, and the formation of subcutaneous collagen and blood vessels. PL@GM could accelerate PU healing by promoting fibroblasts to migrate and secrete collagen and endothelial cells to vascularize. PL@GM promises to be an effective and convenient treatment modality for PU, like chronic wound treatment.

Ferulic acid-g-tamarind gum/guar gum based in situ gel-forming powders as wound dressings

The current research endeavour aimed to synthesize ferulic acid grafted tamarind gum/guar gum (FA-g-TG/GG) based powders as wound dressings, which could form in situ gels upon contact with wound exudates. In this context, variable amounts of FA were initially grafted with TG via the Steglich esterification reaction protocol and the resulting conjugates were subsequently amalgamated with GG and lyophilized to produce dry powders (F-1 – –F-3) with average particle size within 5.10–5.54 μm and average angle of repose ∼30°. These powders were structurally characterized with 1H NMR, FTIR, DSC, TGA, XRD and SEM analyses. Pristine TG, FA-g-TG and FA-g-TG/GG powders (F-2) revealed their distinct morphological structures and variable negative zeta potential values (−11.06 mV–25.50 mV). Among various formulation (F-1–F-3), F-2 demonstrated an acceptable powder-to-gel conversion time (within 20 min), suitable water vapour transmission rates (WVTR, 2564.94 ± 32.47 g/m2/day) and excellent water retention abilities and swelling profiles (4559.00 ± 41.57 %) in wound fluid. The powders were cytocompatible and conferred antioxidant activities. The powders also displayed fibroblast cell proliferation, migration and adhesion properties, implying their wound-healing potentials. Thus, the developed in situ gel-forming powders could be employed as promising dressings for wound management.

Biosynthesis of a Functional Fragment of Human Collagen II in Pichia pastoris.

Collagen II (COL2) is the major component of cartilage tissue and is widely applied in pharmaceuticals, food, and cosmetics. In this study, COL fragments were extracted from human COL2 for secretory expression in Pichia pastoris. Three variants were successfully secreted by shake flask cultivation with a yield of 73.3-100.7 mg/L. The three COL2 variants were shown to self-assemble into triple-helix at 4 °C and capable of forming higher order assembly of nanofiber and hydrogel. The bioactivities of the COL2 variants were validated, showing that sample 205 exhibited the best performance for inducing fibroblast differentiation and cell migration. Meanwhile, sample 205 and 209 exhibited higher capacity for inducing in vitro blood clotting than commercial mouse COL1. To overexpress sample 205, the expression cassettes were constructed with different promoters and signal peptides, and the fermentation condition was optimized, obtaining a yield of 172 mg/L for sample 205. Fed-batch fermentation was carried out using a 5 L bioreactor, and the secretory protease Pep4 was knocked out to avoid sample degradation, finally obtaining a yield of 3.04 g/L. Here, a bioactive COL2 fragment was successfully identified and can be overexpressed in P. pastoris; the variant may become a potential biomaterial for skin care.

Formulation of 1% α-mangostin in orabase gel induces apoptosis in oral squamous cell carcinoma

BackgroundPlant-derived compounds have chemopreventive properties to be used as alternative medicine. Pericarp of Mangosteen (Garcinia mangostana Linn.), a tropical fruit in Southeast Asia contains a phytochemical α-mangostin (α-MG) that demonstrates potent anticancer effects against various types of cancer. α-MG has been reported to be the most effective agent in human cancer cell lines. The objectives of this study were to develop oral gel formulations containing α-MG and determine their (1) anticancer activity, (2) anti-HPV-16 and antimicrobial activities, (3) nitric oxide (NO) inhibitory activity, and (4) wound healing effect.MethodsFormulations of oral gel containing α-MG were developed. Anticancer activity on SCC-25 was assessed. Apoptotic induction was determined using flow cytometry technique. Antiviral activity against HPV-16 pseudovirus and antimicrobial activity against S. mutans, P. gingivalis and C. albicans were investigated. NO inhibition was carried out. Fibroblast cell migration was determined by in vitro scratch assay.ResultsThe formulation of 1% α-MG in orabase gel demonstrated anticancer activity by promoting apoptosis in SCC-25. The induction of apoptotic activity was dose dependent with pronounced effect in late apoptosis. The formulation appeared to reduce cell viability of oral keratinocytes (OKC). At CC50 it showed an inhibition against HPV-16 pseudovirus infection. The formulation had no antimicrobial activity against S. mutans, P. gingivalis and C. albicans. No significant NO inhibitory activity and wound healing effects were found.Conclusions1% α-MG in orabase gel exhibited anticancer activity by inducing apoptosis although low level of cytotoxicity observed in OKC was present. The appropriate carrier for novel nano-particles targeting cancer cells should be further investigated.

Injectable Tissue Adhesive Microgel Composite Containing Antifibrotic Drug for Vocal Fold Scarring.

Vocal fold (VF) scarring, a complex problem in laryngology, results from injury and inflammation of the layered architecture of the VFs. The resultant voice hoarseness, for which successful therapeutic options are currently limited, affects the patient's quality of life. A promising strategy to reverse this disorder is the use of antifibrotic drugs. The present study proposes a novel microbead-embedded injectable hydrogel that can sustain the release of the anti-fibrotic drug pirfenidone (PFD) for vocal fold scarring. Microbeads were developed using sodium alginate and gelatin, which were further embedded into a biomimetic and tissue adhesive gellan gum (GG) hydrogel. The microbead-embedded hydrogel exhibited improved injectability, viscoelasticity, tissue adhesiveness, degradability, and swelling compared to the hydrogel without beads. Additionally, the bead-embedded hydrogel could sustain the release of the PFD for a week. In vitro studies showed that the drug-loaded hydrogel could reduce the migration and proliferation of fibroblast cells in a dose-dependent manner. In summary, this study demonstrates the potential of a PFD-loaded injectable hydrogel with enhanced viscoelastic and tissue-adhesive properties for vocal fold scarring applications.

Targeting the Epigenome Reduces Keloid Fibroblast Cell Proliferation, Migration, and Invasion

Keloids are pathological fibroproliferative scars resulting from abnormal collagen deposition within and beyond the margins of the initial cutaneous insult. Keloids negatively impact quality of life functionally and cosmetically, with current treatment modalities unsatisfactory. Recent studies indicate that epigenetic dysregulation is central to the development and progression of keloids. Here we evaluate the functional significance of epigenetic targeting strategies in vitro using patient-derived keloid fibroblasts treated with small molecule inhibitors of HDACs, LSD1, CoREST and p300, as potential therapies for keloids. We find that both the dual-acting CoREST inhibitor, corin, and the HDAC inhibitor, entinostat, reduce fibroblast proliferation more than the LSD1 inhibitor, GSK-LSD1; additionally, corin was the most effective inhibitor of migration and invasion across keloid fibroblasts. RNA-seq analysis of keloid fibroblasts treated with corin demonstrates coordinate upregulation of many genes including key mediators of cell adhesion such as claudins. Corin also downregulates gene sets involved in cell cycle progression, including reduced expression of cyclins A1 and B2 compared to DMSO. These results highlight a significant role for epigenetic regulation of pathologic mediators of keloidal scarring and suggest that inhibitors of the epigenetic CoREST repressor complex may prove beneficial in the prevention and/or treatment of keloidal scarring in patients.

Expression of a kinase inactive SLK is embryonic lethal and impairs cell migration in fibroblasts

Kinases are known to have kinase activity independent functions. To gain further insights into potential kinase-independent functions of SLK/STK2, we have developed a kinase-dead allele, SLKK63R using in vivo CRISPR/Cas technology. Our studies show that blastocysts homozygote for SLKK63R do not develop into viable mice. However, heterozygotes are viable and fertile with no overt phenotypes. Analyses of mouse embryonic fibroblasts show that expression of SLKK63R results in a 50% decrease in kinase activity in heterozygotes. In contrast to previous studies, our data show that SLK does not form homodimers and that the kinase defective allele does not act in a dominant negative fashion. Expression of SLKK63R leads to altered Rac1 and RhoA activity, increased stress fiber formation and delayed focal adhesion turnover. Our data support a previously observed role for SLK in cell migration and suggest that at least 50% kinase activity is sufficient for embryonic development.

Dielectrophoresis as an Adjunctive Technique for Fibroblast Cell Migration to Enhance Wound Closure

This study reports on DEP-based simulation and experimental validation of polystyrene (PS) beads and fibroblast cells for primary skin cell migration for enhancing wound closure. MyDEP software was used to calculate the numerical simulation of the Clausius-Mossotti factor (CMF). In order to examine particle trajectories based on input frequencies, the finite element technique (FEM) is used. The trajectories of PS beads and fibroblast cells were experimentally assessed to verify the impact of frequency applied on the polarisation of PS beads and fibroblast cells. The outcome illustrated the potential of employing FDEP to move particles and cells to regions of high and low electric field. Fibroblast cells exhibit negative dielectrophoresis (NDEP) at a broad range of frequencies. Thus, FDEP can be utilised for frequency optimisation to enhance wound closure.

BMP1 Promotes Keloid by Inducing Fibroblast Inflammation and Fibrogenesis.

Keloid is a typical fibrotic and inflammatory skin disease with unclear mechanisms and few therapeutic targets. In this study, we found that BMP1 was significantly increased in a collagen high-expressing subtype of fibroblast by reanalyzing a public single-cell RNA-sequence data set of keloid. The number of BMP1-positive fibroblast cells was increased in keloid fibrotic loci. Increased levels of BMP1 were further validated in the skin tissues and fibroblasts from keloid patients. Additionally, a positive correlation between BMP1 and the Keloid Area and Severity Index was found in keloid patients. In vitro analysis revealed collagen production, the phosphorylation levels of p65, and the IL-1β secretion decreased in BMP1 interfered keloid fibroblasts. Besides, the knockdown of BMP1 inhibited the growth and migration of keloid fibroblast cells. Mechanistically, BMP1 inhibition downregulated the noncanonical TGF-β pathways, including p-p38 and p-ERK1/2 signaling. Furthermore, we found the delivery of BMP1 siRNAs could significantly alleviate keloid in human keloid-bearing nude mice. Collectively, our results indicated that BMP1 exhibited various pathogenic effects on keloids as promoting cell proliferation, migration, inflammation, and ECM deposition of fibroblast cells by regulating the noncanonical TGF-β/p38 MAPK, and TGF-β/ERK pathways. BMP1-lowing strategies may appear as a potential new therapeutic target for keloid.

Effect of Multiple-Cycle Collections of Conditioned Media from Different Cell Sources towards Fibroblasts in In Vitro Wound Healing Model.

Conditioned media refers to a collection of the used cell culture media. The goal of this study was to evaluate the possible impacts of different conditioned media collected across a number of cycles on the fibroblast proliferation, migration, and profiles of protein release. Human dermal fibroblast (HDF) cells and Wharton jelly mesenchymal stem cells (WJMSC) were cultured and incubated for 3 days prior to being harvested as cycle-1 using the serum-free media F12:DMEM and DMEM, respectively. The procedures were repeatedly carried out until the fifth cycle of conditioned media collection. An in-vitro scratch assay was conducted to measure the effectiveness of wound healing. Collagen hydrogel was combined separately with both the Wharton jelly-conditioned medium (WJCM) and the dermal fibroblast-conditioned medium (DFCM) in order to evaluate the protein release profile. The conditioned medium from many cycles had a lower level of fibroblast attachment than the control (complete medium); however, the growth rate increased from 100 to 250 h-1, when supplemented with a conditioned medium collected from multiple cycles. The wound scratch assay showed that fibroblast cell migration was significantly increased by repeating cycles up to cycle-5 of DFCM, reaching 98.73 ± 1.11%. This was faster than the rate of migration observed in the cycle-5 of the WJCM group, which was 27.45 ± 5.55%. Collagen hydrogel from multiple cycles of DFCM and WJCM had a similar protein release profile. These findings demonstrate the potential for employing repeated cycles of DFCM- and WJCM-released proteins with collagen hydrogel for applications in wound healing.

Analysis of Enhanced Wound Closure Potential of ADSC-Derived Secretome Compared to Aquacel Extra in Diabetic Rats

Background: Diabetes Mellitus (DM) can lead to serious complications, such as Diabetic Foot Ulcers (DFUs). Currently, Aquacel Extra is one of the standard therapies for DFUs, but its efficacy has some limitations that may be overcome by alternative treatments, such as the secretome derived from Adipose-Derived Stem Cells (ADSCs). ADSC secretome has shown promising results in promoting wound healing by enhancing cell proliferation, collagen synthesis, and migration of fibroblasts. Aims: This study aims to compare the effect of the adipose-derived stem cell (ADSC) secretome to Aquacel Extra, a hydrofiber dressing containing gel-forming agents, on wound healing in a diabetic rat model. Aquacel Extra has sodium carboxymethylcellulose fibers, which contribute to its unique properties. Objective: The objective of this study is to compare the wound healing outcome of ADSC secretome and Aquacel Extra in streptozotocin-induced diabetic rats. Methods: Sprague Dawley rats received a single intravenous administration of streptozotocin to induce diabetes mellitus (DM). A full-thickness excisional circular wound was created at the dorsum aspect of the rats two weeks after diabetic induction. Rats were randomly divided into two groups: the Aquacel Extra group, which received the hydrofiber dressing Aquacel Extra containing gel-forming agents, and the secretome group, which received the ADSC secretome on days 0, 3, and 7. The gross examination was performed on days 0, 3, 7, and 14. On day 14, the rats were euthanized, and full-thickness skin biopsies of the wounds were taken for histological and immunohistochemical analysis. Results: The secretome group demonstrated accelerated cutaneous wound healing compared to the Aquacel Extra group, as indicated by faster wound closure (p < 0.05). Hematoxylin and eosin staining revealed a thicker epidermal layer in the secretome group than in the Aquacel Extra group (p < 0.05). The mean histological score of the secretome group was higher at 10 ± 1.73 compared to the score of 8.33 ± 1.52 in the Aquacel Extra group, indicating a more mature tissue architecture. Immunohistochemical analysis showed lower expression of α-smooth muscle actin (α-sma) in the secretome group than in the Aquacel Extra group, which correlated with reduced collagen secretion and deposition in the secretome group, as indicated by Masson’s trichrome staining. Conclusion: The ADSC secretome accelerated the healing of diabetic wounds compared to Aquacel Extra. However, as this study is preliminary, future studies should be conducted similar to this study with a larger sample and wound size. In addition, the optimal dosage of ADSC secretome and the components of the secretome that promoted wound healing should be determined to fully elucidate the clinical potential of ADSC secretome.