Myofibroblasts: Function, Formation, and Scope of Molecular Therapies for Skin Fibrosis

MicroRNA-541-3p/Rac2 signaling bridges radiation-induced lung injury and repair

Background

While radiation-induced lung injury decreases quality of life and suppresses efficacy of radiotherapy, to date, the relationship between radiation-induced lung injury and repair remains unclear. Our previous studies revealed that TNFRSF10B-RIPK1/RIPK3-MLKL signaling induces necroptosis of alveolar epithelial cells and potentiates radiation-induced lung injury. We also found that microRNA-541-3p is differentially expressed in radiation-damaged lungs. The connection between microRNA-541-3p, TNFRSF10B signaling, and TGFβ1 signaling is also unclear.

Objective

This study was performed to explore the regulatory effects of microRNA-541-3p on TNFRSF10B and TGFβ1 signaling.

Methods

Mouse alveolar epithelial cells were transfected with a vector expressing microRNA-541-3p to regulate expression of target genes. Flow cytometry, polymerase chain reaction, and western blotting were used to analyze cell necroptosis, target gene expression, and target protein expression, respectively.

Results

Overexpression of microRNA-541-3p positively regulated TNFRSF10B-RIPK1/RIPK3-MLKL signaling through Rac2 to induce cell necroptosis. MicroRNA-541-3p negatively regulates Rac2. MicroRNA-541-3p and Rac2 regulate the expression of Tgf-beta1 and its encoded proteins.

Conclusions

The Rac2 gene synchronously regulates TNFRSF10B-RIPK1/RIPK3-MLKL and TGFβ1 signaling. MicroRNA-541-3P/Rac2 act as mediators of radiation damage and repair signaling.

Mechanisms of pulmonary fibrosis and lung cancer induced by chronic PM2.5 exposure: Focus on the airway epithelial barrier and epithelial-mesenchymal transition

This study aims to provide new insights into PM2.5-induced lung diseases through a focus on the pulmonary epithelial barrier and epithelial-mesenchymal transition (EMT). Firstly, we analyzed the mechanisms by which PM2.5 damages the airway epithelial barrier, including inflammatory responses, immune imbalance, oxidative stress, apoptosis, and autophagy. Subsequently, we investigated the mechanisms by which PM2.5 induces EMT, which involve the synergistic effect of oxidative stress and inflammation, the activation of key signaling pathways, and the regulatory role of non-coding RNAs. Furthermore, we explored the interaction between the airway epithelial barrier and EMT, especially the induction of EMT by epithelial barrier damage and the impact of EMT on epithelial barrier repair. Regarding lung injury diseases, we focused on the roles of the epithelial barrier and EMT in the development of pulmonary fibrosis and lung cancer, providing evidence from in vitro and in vivo studies. Emphasizing the translational prospects from basic research to clinical applications, and we proposed new ideas for treating PM2.5-related lung diseases from four aspects-anti-inflammatory and antioxidant drugs, signaling pathway inhibitors, non-coding RNA-targeted therapies, and gene editing and cell therapies-by focusing on the two key links of the airway epithelial barrier and EMT.

Novel high throughput 3D ECM remodeling assay identifies MEK as key driver of fibrotic fibroblast activity

In fibrotic tissues, activated fibroblasts remodel the collagen-rich extracellular matrix (ECM). Intervening with this process represents a candidate therapeutic strategy to attenuate disease progression. Models that generate quantitative data on 3D fibroblast-mediated ECM remodeling with the reproducibility and throughput needed for drug testing are lacking. Here, we develop a model that fits this purpose and produces combined quantitative information on drug efficacy and cytotoxicity. We use microinjection robotics to design patterns of fibrillar collagen-embedded fibroblast clusters and apply automated microscopy and image analysis to quantify ECM remodeling between-, and cell viability within clusters of TGFβ-activated primary human skin or lung fibroblasts. We apply this assay to compound screening and reveal actionable targets to suppress fibrotic ECM remodeling. Strikingly, we find that after an initial phase of fibroblast activation by TGFβ, canonical TGFβ signaling is dispensable and, instead, non-canonical activation of MEK-ERK signaling drives ECM remodeling. Moreover, we reveal that higher concentrations of two TGFβ receptor inhibitors while blocking canonical TGFβ signaling, in fact stimulate this MEK-mediated profibrotic ECM remodeling activity.

Quercetin, Kaempferol and Capsaicin Counteract the TGF-β1-Induced Upregulation of αSMA and Collagen in Myoblasts

In fibrotic skeletal muscles, excessive extracellular matrix (ECM) deposition is a result of increased activation and decreased apoptosis of myofibroblasts. The aim of this study is to investigate whether treatment with quercetin, kaempferol or capsaicin can reduce the transforming growth factor-beta 1 (TGF-β1)-induced myofibroblast differentiation and fibrotic ECM expression in differentiated C2C12 cells. Two-day-differentiated C2C12 cells were treated with TGF-β1 for 48 h to induce myofibroblast differentiation. Twenty-four hours before (pre-treatment) and for forty-eight hours with (co-treatment) TGF-β1 treatment, cells were exposed to quercetin (25, 50 µM), kaempferol (10, 25, 50 µM) or capsaicin (25, 50 µM). The immunofluorescence intensity of alpha smooth muscle actin (αSMA) and collagen type I/III gene expression were assessed as myofibroblast markers. MyoD immunofluorescence intensity was measured as a myogenic marker. Co-treatment of TGF-β1 with the phytochemicals was most effective, resulting in a decreased number of αSMA-positive cells (all three compounds), decreased collagen type I (kaempferol, capsaicin) and type III (kaempferol) gene expression, and increased MyoD (kaempferol, capsaicin) protein expression compared to TGF-β1 treatment. This study demonstrates that treatment with quercetin, kaempferol or capsaicin can reduce myofibroblast markers. This suggests a possible anti-fibrotic effect of the phytochemicals in skeletal muscle.

Nutritional strategies targeting age-related skeletal muscle fibrosis: underlying mechanisms

Aging is associated with a reduced number and function of muscle stem cells (MuSC). This results in a decreased muscle regenerative capacity and increased formation of fibrotic tissue, impairing skeletal muscle function. This review provides an overview of in vitro and in vivo animal studies investigating nutritional interventions with the potential to inhibit pathophysiological mechanisms involved in the development of skeletal muscle fibrosis. Mechanism targets include 1) MuSC function and myogenic differentiation, 2) M1 to M2 macrophage polarization, 3) myofibroblast activity or extracellular matrix (ECM) deposition, and 4) reactive oxygen species (ROS) mediated pathways, such as NOX2/4 activity. Most promising nutrients described in this review are phytonutrients, vitamins and amino acids. Quercetin targets multiple pathways (showing decreased inflammation, ECM expression and NOX2/4 activity) in various cell types and tissues (kidney, aorta, liver and (heart) muscle) of rodents and rabbits, which could contribute to fibrosis development. Additionally, sulforaphane is a promising candidate as it inhibits inflammation, ECM expression, and ROS production in mouse skeletal muscle. After validation of the effects in human skeletal muscle, supplementation with these nutrients could be implemented in a multifaceted intervention (including exercise and adequate protein intake) targeting age-related skeletal muscle fibrosis.

Cellular crosstalk in fibrosis: insights into macrophage and fibroblast dynamics

Pathological fibrosis, the excessive deposition of extracellular matrix and tissue stiffening that causes progressive organ dysfunction, underlies diverse chronic diseases. The fibrotic microenvironment is driven by the dynamic microenvironmental interaction between various cell types; macrophages and fibroblasts play central roles in fibrotic disease initiation, maintenance, and progression. Macrophage functional plasticity to microenvironmental stimuli modulates fibroblast functionality by releasing pro-inflammatory cytokines, growth factors, and matrix remodeling enzymes that promote fibroblast proliferation, activation, and differentiation into myofibroblasts. Activated fibroblasts and myofibroblasts serve as the fibrotic effector cells, secreting extracellular matrix components and initiating microenvironmental contracture. Fibroblasts also modulate macrophage function through the release of their own pro-inflammatory cytokines and growth factors, creating bidirectional crosstalk that reinforces the chronic fibrotic cycle. The intricate interplay between macrophages and fibroblasts, including their secretomes and signaling interactions, leads to tissue damage and pathological loss of tissue function. In this review, we examine macrophage-fibroblast reciprocal dynamic interactions in pathological fibrotic conditions. We discuss the specific lineages and functionality of macrophages and fibroblasts implicated in fibrotic progression, with focus on their signal transduction pathways and secretory signalling that enables their pro-fibrotic behaviour. We then finish with a set of recommendations for future experimentation with the goal of developing a set of potential targets for anti-fibrotic therapeutic candidates. Understanding the cellular interactions between macrophages and fibroblasts provides valuable insights into potential therapeutic strategies to mitigate fibrotic disease progression.

Modeling Stromal Cells Inside the Tumor Microenvironment of Ovarian Cancer: In Vitro Generation of Cancer-Associated Fibroblast-Like Cells and Their Impact in a 3D Model

The tumor microenvironment (TME) is the combination of cells and factors that promotes tumor progression, and cancer-associated fibroblasts (CAFs) are a key component within TME. CAF originates from various stromal cells and is activated by factors such as transforming growth factor-beta (TGF-β) secreted by tumor cells, favoring chemoresistance and metastasis. Recent publications have underlined plasticity and heterogeneity and their strong contribution to the reactive stroma within the TME. Our study aimed to replicate the TME's structure by creating a 3D in vitro model of ovarian cancer (OC). By incorporating diverse tumor and stromal cells, we simulated a physiologically relevant environment for studying CAF-like cell behavior within tumor spheroids in a context-dependent manner. CAF-like cells were generated by exposing human dermal fibroblasts to OC cell line conditioned media in the presence or absence of TGF-β. Herein, we found that different stimuli induce the generation of heterogeneous populations of CAF-like cells. Notably, we observed the ability of CAF-like cells to shape the intratumoral architecture and to contribute to functional changes in tumor cell behavior. This study highlights the importance of precise assessment of CAF for potential therapeutic interventions and further provides a reliable model for investigating novel therapeutic targets in OC.

The Effects of Multicomponent Training on Clinical, Functional, and Psychological Outcomes in Cardiovascular Disease: A Narrative Review

Cardiovascular diseases (CVDs) remain the leading cause of death globally. In recent years, interest in multicomponent interventions has grown as a response to the multifactorial complexity of CVDs. However, the literature still shows little systematic investigation into the effectiveness of multicomponent training (MCT) in the field of CVDs, accompanied by terminological confusion. This study aims to summarize and critically appraise the recent literature through a narrative review. A narrative review was conducted, synthesizing evidence from studies published between 2010 and January 2025. The databases searched included PubMed, Scopus, and Google Scholar using predefined search terms related to CVDs and MCT, and medical subject headings (MeSHs) and Boolean syntax. Two team authors independently extracted relevant information from the included studies. MCT significantly improved hemodynamic parameters in CVD patients, with reductions in systolic, diastolic, mean blood pressure, and heart rate. Physical fitness measures showed consistent enhancements whereas anthropometric improvements often corresponded with blood pressure reductions. Psychological outcomes varied across studies, with intervention duration emerging as a key factor in effectiveness. MCT interventions could lead to improvements in clinical outcomes, risk factor reduction, and patient adherence. Although findings on psychological parameters remain inconsistent, the overall evidence supports their integration into both clinical and community settings.

Autoimmune regulator deficiency causes sterile epididymitis and impacts male fertility through disruption of inorganic physiology

Autoimmune regulator (AIRE), a transcriptional regulator expressed by medullary thymic epithelial cells, is required for shaping the self-antigen tolerant T cell receptor repertoire. In humans, AIRE mutations caues autoimmune polyglandular syndrome type 1. Among other symptoms, men with autoimmune polyglandular syndrome type 1 commonly experience testicular insufficiency and infertility, but the mechanisms causing infertility are unknown. Using an Aire-deficient mouse model, we demonstrate that male subfertility is caused by sterile epididymitis characterized by immune cell infiltration and extensive fibrosis. In addition, we reveal that the presence of autoreactive immune cells and inflammation in epididymides of Aire-deficient mice are required for iron deposition in the interstitium, which is brought on by macrophages. We further demonstrate that male subfertility is associated with a decrease in metals zinc, copper, and selenium, which serve as cofactors in several antioxidant enzymes. We also show an increase in DNA damage of epididymal sperm of Aire-/- animals as a key contributing factor to subfertility. The absence of Aire results in autoimmune attack of the epididymis leading to fibrosis, iron deposition, and copper, zinc, and selenium imbalance, ultimately resulting in sperm DNA damage and subfertility. These results highlight the requirement of Aire to promote immune tolerance to the epididymis, and that its disruption causes an imbalance of inorganic elements with resulting consequence on male fertility.

Fibromodulin selectively accelerates myofibroblast apoptosis in cutaneous wounds by enhancing interleukin 1β signaling

Activated myofibroblasts deposit extracellular matrix material to facilitate rapid wound closure that can heal scarlessly during fetal development. However, adult myofibroblasts exhibit a relatively long life and persistent function, resulting in scarring. Thus, understanding how fetal and adult tissue regeneration differs may serve to identify factors that promote more optimal wound healing in adults with little or less scarring. We previously found that matricellular proteoglycan fibromodulin is one such factor promoting more optimal repair, but the underlying molecular and cellular mechanisms for these effects have not been fully elucidated. Here, we find that fibromodulin induces myofibroblast apoptosis after wound closure to reduce scarring in small and large animal models. Mechanistically, fibromodulin accelerates and prolongs the formation of the interleukin 1β-interleukin 1 receptor type 1-interleukin 1 receptor accessory protein ternary complex to increase the apoptosis of myofibroblasts and keloid- and hypertrophic scar-derived cells. As the persistence of myofibroblasts during tissue regeneration is a key cause of fibrosis in most organs, fibromodulin represents a promising, broad-spectrum anti-fibrotic therapeutic.

RNA-sequencing demonstrates transcriptional differences between human vocal fold fibroblasts and myofibroblasts

BACKGROUND

Differentiation of fibroblasts into myofibroblasts is necessary for wound healing, but excessive myofibroblast presence and persistence can result in scarring. Treatment for scarring is limited largely due to a lack of comprehensive understanding of how fibroblasts and myofibroblasts differ at the transcript level. The purpose of this study was to characterize transcriptional profiles of injured fibroblasts relative to normal fibroblasts, utilizing fibroblasts from the vocal fold as a model.

RESULTS

Utilizing bulk RNA sequencing technology, we identified differentially expressed genes between four cell lines of normal fibroblasts (cVFF), one line of scarred fibroblasts (sVFF), and four lines of fibroblasts treated with transforming growth factor-beta 1 (TGF-β1), representing an induced-scar phenotype (tVFF). Principal component analysis revealed clustering of normal fibroblasts separate from the clustering of fibroblasts treated with TGF-β1; scarred fibroblasts were more similar to normal fibroblasts than fibroblasts treated with TGF-β1. Enrichment analyses revealed pathways related to cell signaling, receptor-ligand activity, and regulation of cell functions in scarred fibroblasts, pathways related to cell adhesion in normal fibroblasts, and pathways related to ECM binding in fibroblasts treated with TGF-β1. Although transcriptomic profiles between scarred fibroblasts and fibroblasts treated with TGF-β1 were relatively dissimilar, the most highly co-expressed genes were enriched in pathways related to actin cytoskeleton binding, which supports the use of fibroblasts treated with TGF-β1 to represent a scarred cell phenotype.

CONCLUSIONS

Transcriptomics of normal fibroblasts differ from myofibroblasts, including from those retrieved from scar and those treated with TGF-β1. Despite large differences in transcriptomics between tVFF and sVFF, tVFF serve as a useful in vitro model of myofibroblasts and highlight key similarities to myofibroblasts extracted from scar pathology, as well as expected differences related to normal fibroblasts from healthy vocal folds.

Extracellular Matrix Stiffness: Mechanotransduction and Mechanobiological Response-Driven Strategies for Biomedical Applications Targeting Fibroblast Inflammation

The extracellular matrix (ECM) is a dynamic network providing mechanical and biochemical cues that regulate cellular behavior. ECM stiffness critically influences fibroblasts, the primary ECM producers, particularly in inflammation and fibrosis. This review explores the role of ECM stiffness in fibroblast-driven inflammation and tissue remodeling, focusing on the physicochemical and biological mechanisms involved. Engineered materials, hydrogels, and polydimethylsiloxane (PDMS) are highlighted for replicating tissue-specific stiffness, enabling precise control over cell-matrix interactions. The surface functionalization of substrate materials, including collagen, polydopamine, and fibronectin, enhances bioactivity and fibroblast adhesion. Key mechanotransduction pathways, such as integrin signaling and YAP/TAZ activation, are related to regulating fibroblast behaviors and inflammatory responses. The role of fibroblasts in driving chronic inflammatory diseases emphasizes their therapeutic potentials. Advances in ECM-modifying strategies, including tunable biomaterials and hydrogel-based therapies, are explored for applications in tissue engineering, drug delivery, anti-inflammatory treatments, and diagnostic tools for the accurate diagnosis and prognosis of ECM stiffness-related inflammatory diseases. This review integrates mechanobiology with biomedical innovations, providing a comprehensive prognosis of fibroblast responses to ECM stiffness and outlining future directions for targeted therapies.

ARP2/3 complex affects myofibroblast differentiation and migration in pancreatic ductal adenocarcinoma

The ARP2/3 complex, which orchestrates actin cytoskeleton organization and lamellipodia formation, has been implicated in the initiation of pancreatic ductal adenocarcinoma (PDAC). This study aims to clarify its impact on the activity of cancer-associated fibroblasts (CAFs), key players in PDAC progression, and patient outcomes. Early pancreatic carcinogenesis was modeled in p48Cre; LSL-KrasG12D mice with caerulein-induced pancreatitis, complemented by in vitro studies on human immortalized pancreatic stellate cells (PSCs) and primary PDAC-derived CAFs. Data were gained from microarray analysis, RNA sequencing (RNA-seq), and single-cell RNA sequencing (sc-RNA-seq), with subsequent bioinformatics analysis. We uncovered a specific transcriptional signature associated with fibroblast migration in early pancreatic carcinogenesis and linked it to poor survival in patients with PDAC. A pivotal role of the ARP2/3 complex in CAF migration was identified. Inhibition of the ARP2/3 complex markedly decreased CAF motility and induced significant morphological changes in vitro. Furthermore, its inhibition also hindered TGFβ1-mediated myofibroblastic CAF differentiation but had no effect on IL-1-mediated inflammatory CAF differentiation. Our findings position the ARP2/3 complex as central to the migration and differentiation of myofibroblastic CAF. Targeting this complex presents a promising new therapeutic avenue for PDAC treatment.

LINC00525 promotes cell proliferation and collagen expression through feedforward regulation of TGF-β signaling in hypertrophic scar fibroblasts

The etiology of hypertrophic scar formation continues to elude researchers, despite advancements in the understanding of skin scarring. Several long non-coding RNAs (lncRNAs) have been implicated in the pathogenesis of hypertrophic scars, yet the role and molecular mechanisms of LINC00525 in this process remain unclear. This study demonstrates that LINC00525 enhances cell proliferation and collagen expression through knockdown and overexpression techniques. Further analysis, including nuclear and cytoplasmic localization studies, RNA pull-down assays, bioinformatics predictions, and PCR validation, reveals that LINC00525 interacts with miR-29a-5p. The downregulation of LINC00525 enhances the expression of miR-29a-5p and suppresses the TGF-β/Smad signaling pathway. Additionally, TGF-β1 induces the upregulation of LINC00525. Collectively, these findings indicate that LINC00525 operates through a feedforward mechanism to regulate TGF-β signaling in hypertrophic scar fibroblasts. This research offers novel insights for the prevention and treatment of scars.

Development of a biomarker panel for cell characterization intended for cultivated meat

Cultivated meat has in recent years been suggested as a sustainable alternative to produce meat at large-scale. Several aspects of cultivated meat production have demonstrated significant progress. However, there are still many questions regarding the cell culture, media composition, and the production itself to be answered and optimized. Finding good starter cell populations is a challenge to address and requires robust tools to characterize the cell populations. Detailed analysis is required to identify each type of cell within the skeletal muscle niche leads to optimized cultivated meat production at large-scale. In this study, we developed a set of biomarkers, using digital droplet PCR (ddPCR) and Immunofluorescence (IF) staining, to identify specific cell types within a heterogeneous cell population isolated from skeletal muscle tissue. We showed that combining Neural Cell Adhesion Molecule (NCAM), Calponin 1 (CNN1), and Fibronectin (FN), can be a powerful approach to predict the growth of skeletal myotubes, smooth muscle mesenchymal cells (SMMCs), and myofibroblasts, respectively. Moreover, early cell-cell interactions of fibroblastic cells were observed to be triggered through thin actin filaments containing CNN1 protein, to form, subsequently, myofibroblast networks. Besides, Myogenic Differentiation 1 (MyoD) is the key marker to detect skeletal muscle growth, whereas Myogenic Factor 5 (MyF5) can be expressed in myogenic and non-myogenic cells. MyF5 was detected at differentiation stages within the myotube nuclei, suggesting an unknown role during myotube formation.

Long QT syndrome type 3 gain-of-function of Nav1.5 increases ventricular fibroblasts proliferation and pro-fibrotic factors

The long QT syndrome type 3 (LQT3) is a cardiac channelopathy caused by gain-of-function mutations in the SCN5A gene, encoding the sodium channel Nav1.5. As Nav1.5 is expressed in cardiomyocytes but also in cardiac fibroblasts, we investigated whether the LQT3-causing p.ΔQKP1507-1509 (ΔQKP) SCN5A mutation alters cardiac fibroblast phenotype. Primary cultured ventricular fibroblasts from Scn5a+/ΔQKP knock-in mice showed increased proliferation, survival, expression of transforming growth factor-β (TGF-β) and activation of its canonical pathway, and reduced α-smooth muscle actin expression. Ventricular tissue from Scn5a+/ΔQKP mice exhibited augmented fibroblast populations and fibrosis. Inhibiting TGF-β receptor, sodium current or Scn5a expression decreased Scn5a+/ΔQKP fibroblast proliferation, while veratridine increased proliferation of control fibroblasts, mimicking Nav1.5 gain-of-function. Lastly, abnormal calcium signaling underlied the increased proliferation of Scn5a+/ΔQKP fibroblasts. Our study shows that cardiac fibroblasts carrying the ΔQKP-SCN5A mutation exhibit an abnormal, proliferative phenotype, paving the way for better understanding the role of cardiac fibroblasts in LQT3.

Next-Generation Biomaterials for Wound Healing: Development and Evaluation of Collagen Scaffolds Functionalized with a Heparan Sulfate Mimic and Fibroblast Growth Factor 2

Fibrosis after full-thickness wound healing-especially after severe burn wounds-remains a clinically relevant problem. Biomaterials that mimic the lost dermal extracellular matrix have shown promise but cannot completely prevent scar formation. We present a novel approach where porous type I collagen scaffolds were covalently functionalized with ReGeneRating Agent (RGTA®) OTR4120. RGTA® is a glycanase-resistant heparan sulfate mimetic that promotes regeneration when applied topically to chronic wounds. OTR4120 is able to capture fibroblast growth factor 2 (FGF-2), a heparan/heparin-binding growth factor that inhibits the activity of fibrosis-driving myofibroblasts. Scaffolds with various concentrations and distributions of OTR4120 were produced. When loaded with FGF-2, collagen-OTR4120 scaffolds demonstrated sustained release of FGF-2 compared to collagen-heparin scaffolds. Their anti-fibrotic potential was investigated in vitro by seeding primary human dermal fibroblasts on the scaffolds followed by stimulation with transforming growth factor β1 (TGF-β1) to induce myofibroblast differentiation. Collagen-OTR4120(-FGF-2) scaffolds diminished the gene expression levels of several myofibroblast markers. In absence of FGF-2 the collagen-OTR4120 scaffolds displayed an inherent anti-fibrotic effect, as the expression of two fibrotic markers (TGF-β1 and type I collagen) was diminished. This work highlights the potential of collagen-OTR4120 scaffolds as biomaterials to improve skin wound healing.

Spiny mice (Acomys) have evolved cellular features to support regenerative healing

Spiny mice (Acomys spp.) are warm-blooded (homeothermic) vertebrates whose ability to restore missing tissue through regenerative healing has coincided with the evolution of unique cellular and physiological adaptations across different tissue types. This review seeks to explore how these bizarre rodents deploy unique or altered injury response mechanisms to either enhance tissue repair or fully regenerate excised tissue compared to closely related, scar-forming mammals. First, we examine overall trends in healing Acomys tissues, including the cellular stress response, the ability to activate and maintain cell cycle progression, and the expression of certain features in reproductive adults that are normally associated with embryos. Second, we focus on specific cell types that exhibit precisely regulated proliferation to restore missing tissue. While Acomys utilize many of the same cell types involved in scar formation, these cells exhibit divergent activation profiles during regenerative healing. Considered together, current lines of evidence support sustained deployment of proregenerative pathways in conjunction with transient activation of fibrotic pathways to facilitate regeneration and improve tissue repair in Acomys.

Induction of Fibroblast-to-Myofibroblast Differentiation by Changing Cytoplasmic Actin Ratio

Myofibroblasts, which play a crucial role in the tumour microenvironment, represent a promising avenue for research in the field of oncotherapy. This study investigates the potential for the induced differentiation of human fibroblasts into myofibroblasts through downregulation of the γ-cytoplasmic actin (γ-CYA) achieved by RNA interference. A decrease in the γ-CYA expression in human subcutaneous fibroblasts resulted in upregulation of myofibroblast markers, including α-smooth muscle actin (α-SMA), ED-A FN, and type III collagen. These changes were accompanied by notable alterations in cellular morphology, characterized by a significant increase in cell area and the formation of pronounced supermature focal adhesions. Downregulation of γ-CYA resulted in the compensatory increase in expression of the β-cytoplasmic actin and α-SMA, and formation of the characteristic α-SMA-positive stress fibers. In conclusion, our results demonstrate that a decrease in the γ-CYA expression leads to myofibroblastic trans-differentiation of human subcutaneous fibroblasts.

Methylglyoxal-Stimulated Mesothelial Cells Prompted Fibroblast-to-Proto-Myofibroblast Transition

During long-term peritoneal dialysis, peritoneal fibrosis (PF) often happens and results in ultrafiltration failure, which directly leads to the termination of dialysis. The accumulation of extracellular matrix produced from an increasing number of myofibroblasts was a hallmark characteristic of PF. To date, glucose degradation products (GDPs, i.e., methylglyoxal (MGO)) that appeared during the heating and storage of the dialysate are considered to be key components to initiating PF, but how GDPs lead to the activation of myofibroblast in fibrotic peritoneum has not yet been fully elucidated. In this study, mesothelial cell line (MeT-5A) and fibroblast cell line (MRC-5) were used to investigate the transcriptomic and proteomic changes to unveil the underlying mechanism of MGO-induced PF. Our transcriptomic data from the MGO-stimulated mesothelial cells showed upregulation of genes involved in pro-inflammatory, apoptotic, and fibrotic pathways. While no phenotypic changes were noted on fibroblasts after direct MGO, supernatant from MGO-stimulated mesothelial cells promoted fibroblasts to change into proto-myofibroblasts, activated fibroblasts in the first stage toward myofibroblasts. In conclusion, this study showed that MGO-stimulated mesothelial cells promoted fibroblast-to-proto-myofibroblast transition; however, additional involvement of other factors or cells (e.g., macrophages) may be needed to complete the transformation into myofibroblasts.

Autoimmune regulator deficiency causes sterile epididymitis and impacts male fertility through disruption of inorganic physiology

Autoimmune regulator (AIRE), a transcription factor expressed by medullary thymic epithelial cells, is required for shaping the self-antigen tolerant T cell receptor repertoire. Humans with mutations in AIRE suffer from Autoimmune Polyglandular Syndrome Type 1 (APS-1). Among many symptoms, men with APS-1 commonly experience testicular insufficiency and infertility, but the mechanisms causing infertility are unknown. Using an Aire -deficient mouse model, we demonstrate that male subfertility is caused by sterile epididymitis characterized by immune cell infiltration and extensive fibrosis. In addition, we reveal that the presence of autoreactive immune cells and inflammation in epididymides of Aire- deficient mice are required for iron (Fe) deposition in the interstitium, which is brought on by macrophages. We further demonstrate that male subfertility is associated with a decrease in metals zinc (Zn), copper (Cu), and selenium (Se) which serve as cofactors in several antioxidant enzymes. We also show increase in DNA damage of epididymal sperm of Aire -/- animals as a key contributing factor to subfertility. The absence of Aire results in autoimmune attack of the epididymis leading to fibrosis, Fe deposition, and Cu, Zn and Se imbalance, ultimately resulting in sperm DNA damage and subfertility. These results highlight the requirement of Aire to promote immune tolerance throughout the epididymis, disruption of which causes an imbalance of inorganic elements with resulting consequence on male fertility.

Key points

Breakdown of epididymal self-tolerance promotes disruption of inorganic elements. Autoimmunity causes interstitial fibrosis resulting in sperm DNA damage and subfertility. Elevated interstitial iron and macrophages contribute to fibrosis.

Transcriptome and Proteome Analysis Identify Decorin as a Principal Antifibrotic Component Trapping TGF‐β1 Within Adipose‐Derived Stem Cell Secretome

Adipose‐derived stem cells (ADSCs) demonstrated therapeutic potential in various fibrotic diseases, with their paracrine proteins playing a crucial role. Nonetheless, the principal paracrine factors of ADSCs responsible for antifibrosis have not yet been well identified. To address this issue, we initially confirmed that ADSCs could attenuate fibrosis and suppress TGF‐β1 in bleomycin‐induced skin fibrosis mouse models. RNA‐sequencing of the cocultured fibroblasts demonstrated that ADSCs effectively inhibited the TGF‐β/Smad2 signaling pathway in fibroblasts through the paracrine approach. Proteomic analysis of the cell supernatant (CS) demonstrated a significant upregulation of 97 proteins in the secretome of ADSCs, among which decorin (DCN) exhibited a particularly elevated level of overexpression. Protein–protein interaction (PPI) network analysis indicated a strong correlation between DCN and TGF‐β1, with DCN effectively trapping TGF‐β1 through core protein binding. Cell experiments demonstrated that DCN could effectively inhibit TGF‐β1‐induced fibroblast proliferation. Therefore, it was concluded that DCN was a crucial protein in ADSC secretome that exerted antifibrotic effects by inhibiting TGF‐β1. This study conducted an in‐depth insight into the paracrine function of ADSCs through transcriptome and proteome analysis, identifying DCN as an essential paracrine factor mediating the antifibrotic effect of ADSCs, which could provide valuable theoretical support for the use of ADSC secretions as well as DCN in the treatment of fibrotic diseases.

Topography immune-responsive silk films for skin regeneration

Scar formation and chronic refractory wounds pose a significant threat to public health, with abnormal immune regulation as a key characteristic. However, topography, a crucial factor influencing immune responses, has not been adequately considered in the design of wound dressings. In this study, we constructed a hierarchical structure on silk fibroin (SF) films by combining soft lithography and femtosecond laser ablation, without altering the intrinsic properties of SF. The discontinuity in the hierarchical structure induced a transformation in the morphology of macrophage RAW264.7 cells from round to spindle or pancake-like shapes, leading to phenotypic polarization toward M2 or M1. The timely transition from M1 to M2 polarization and the balance between these states promoted fibroblast L929 cells to express mRNA for FN, coll-I, TGF-β1, and α-SMA. The hierarchical structure of SF films facilitates full-thickness wound repair in vivo by regulating inflammation and promoting neovascularization and collagen deposition. Thus, hierarchical topography presents a promising strategy for the design of immunomodulatory wound dressings.

Potential of Plant-derived Exosome-like Nanoparticles from Physalis peruviana Fruit for Human Dermal Fibroblast Regeneration and Remodeling

AIMS

This research aimed to study the potential of PDEN from P. peruviana fruits (PENC) for regenerating and remodeling HDF.

BACKGROUND

Large wounds are dangerous and require prompt and effective healing. Various efforts have been undertaken, but have been somewhat ineffective. Plant-derived exosome-like nanoparticles (PDEN) are easily sampled, relatively cost-effective, exhibit high yields, and are nonimmunogenic.

OBJECTIVES

The objective of the study was to isolate and characterize PDEN from Physalis peruviana (PENC), and determine PENC's internalization and toxicity on HDF cells, PENC's ability to regenerate HDF (proliferation and migration), and PENC ability's to remodel HDF (collagen I and MMP-1 production).

METHODS

PENC was isolated using gradual filtration and centrifugation, followed by sedimentation using PEG6000. Characterization was done using a particle size analyzer, zeta potential analyzer, TEM, and BCA assay. Internalization was done using PKH67 staining. Toxicity and proliferation assays were conducted using MTT assay; meanwhile, migration assay was carried out by employing the scratch assay. Collagen I production was performed using immunocytochemistry and MMP-1 production was conducted using ELISA.

RESULTS

MTT assay showed a PENC concentration of 2.5 until 500 μg/mL and being non-toxic to cells. PENC has been found to induce cell proliferation in 1, 3, 5, and 7 days. PENC at a concentration of 2.5, 5, and 7.5 μg/mL, also accelerated HDF migration using the scratch assay in two days. In remodeling, PENC upregulated collagen-1 expression from day 7 to 14 compared to control. MMP-1 declined from day 2 to 7 in every PENC concentration and increased on day 14. Overall, PENC at concentrations of 2.5, 5, and 7.5 μg/mL induced HDF proliferation and migration, upregulated collagen I production, and decreased MMP-1 levels.

CONCLUSION

Isolated PENC was 190-220 nm in size, circular, covered with membrane, and its zeta potential was -6.7 mV; it could also be stored at 4°C for up to 2 weeks in aqua bidest. Protein concentration ranged between 170-1,395 μg/mL. Using PKH67, PENC could enter HDF within 6 hours. PENC was non-toxic up to a concentration of 500 μg/mL. Using MTT and scratch assay, PENC was found to elevate HDF proliferation and migration, and reorganize actin. Using immunocytochemistry, collagen I was upregulated by PENC, whereas MMP-1 concentration was reduced.

Construction of piezoelectric, conductive and injectable hydrogels to promote wound healing through electrical stimulation

Piezoelectric, conductive, and injectable hydrogel (SPG hydrogel) is constructed to rapidly close wounds, efficiently harvest biomechanical energy from animal motion, and generate electrical stimulation for electrotherapy of wound healing. 3-amino-4-methoxybenzoic acid (AMB) monomer was polymerized and grafted onto the gelatin, which was further crosslinked using EDC/NHS and embedded with strontium titanate nanoparticles (80.5 wt%), forming SPG hydrogel. This SPG hydrogel had high tissue adhesion ability, and could generate the output voltage (maximum output voltage 1 V) and current (maximum output current 0.5 nA) upon mechanical bending, promoting NIH-3T3 cell migration and proliferation. Upon application to the mice wound model, the SPG hydrogel rapidly closed the skin wound, smoothed the wound's appearance, reduced the remaining wound size, and increased epidermal thickness, demonstrating remarkable wound healing capabilities. This study suggests that the body motion-promoted electrotherapy offers a promising strategy for wound healing. STATEMENT OF SIGNIFICANCE: Piezoelectric nanomaterials are often incorporated into hydrogels to create piezoelectric hydrogels for wound healing. However, piezoelectric nanomaterials tend to agglomerate within the hydrogel matrix, and the hydrogel's low conductivity hinders efficient electron transfer. Together, both factors significantly reduce the piezoelectric effect. In this study, we developed an SPG hydrogel to improve the homogeneity and conductivity of the piezoelectric hydrogel. We first designed a conductive PG hydrogel and then immoblized piezoelectric STO nanoparticles within its matrix through coordination chemistry. Upon mechanical deformation, the uniformly distributed STO nanoparticles can generate electricity, which can efficiently transfer through the conductive matrix to the hydrogel's surface. This design shows great potential for wound healing applications.

Bone morphogenetic protein-3 is a negative regulator of transforming growth factor beta and fibrosis

Fibrosis results in one-third of all deaths globally and is a major healthcare challenge. Fibrosis is scarring caused by the excess deposition of extracellular matrix proteins by fibroblasts. Inhibition of pathways downstream of transforming growth factor β (TGF-β) a pluripotent growth factor, has potent antifibrotic effects in different organs. Here we show that loss of bone morphogenetic protein (BMP-3) is a feature of kidney fibrosis, independent of the initiating injury, suggesting loss of this cytokine is a core fibrotic mechanism. TGF-β decreased BMP3 expression in human fibroblasts is possibly a feed-forward loop that contributes to increased and sustained TGF-β activity. Recombinant human BMP-3 reduced TGF-β induced fibroblast contraction, migration and invasion, pathways that lead to scarring and tissue stiffening. BMP-3 reduced TGF-β stimulated collagen cross-linking, and Ox-LDL receptor 1, a regulator of collagen deposition. BMP-3 inhibited TGF-β stimulated lysyl oxidase activity. Lysyl oxidase mediated collagen cross-linking is a critical process in TGF-β induced fibrosis. We propose that BMP-3 alters fibroblast responses to TGF-β, shifting the balance from fibrosis to repair. Recombinant human BMP-3 shows promise for development as a novel therapeutic for fibrosis.

Development of immunocompetent full thickness skin tissue constructs to model skin fibrosis for high-throughput drug screening

The lack of the immune component in most of the engineered skin models remains a challenge to study the interplay between different immune and non-immune cell types of the skin. Immunocompetent humanin vitroskin models offer potential advantages in recapitulatingin vivolike behavior which can serve to accelerate translational research and therapeutics development for skin diseases. Here we describe a three-dimensional human full-thickness skin (FTS) equivalent incorporating polarized M1 and M2 macrophages from human peripheral CD14+monocytes. This macrophage-incorporated FTS model demonstrates discernible immune responses with physiologically relevant cytokine production and macrophage plasticity under homeostatic and lipopolysaccharide stimulation conditions. M2-incorporated FTS recapitulates skin fibrosis phenotypes with transforming growth factor-β1 treatment as reflected by significant collagen deposition and myofibroblast expression, demonstrating a M2 potentiation effect. In conclusion, we successfully biofabricated an immunocompetent FTS with functional macrophages in a high-throughput (HT) amenable format. This model is the first step towards a HT-assay platform to develop new therapeutics for skin diseases.

Advanced repair of recurrent and low-large hysterotomy defects using a myometrial glide flap

BACKGROUND

The resolution of factors linked to the recurrence of cesarean section defects can be accomplished through a comprehensive technique that effectively addresses the dehiscent area, eliminates associated intraluminal fibrosis, and establishes a vascularized anterior wall by creating a sliding myometrial flap.

OBJECTIVE

Propose a comprehensive surgical repair for recurrent and large low hysterotomy defects in women seeking pregnancy or recurrent spotting.

STUDY DESIGN

A retrospective cohort analysis included 54 patients aged 25-41 with recurrent large cesarean scar defects treated at Otamendi, CEMIC, and Valle de Lili hospitals. Comprehensive surgical repair was performed by suprapubic laparotomy, involving a wide opening of the vesicouterine space, removal of the dehiscent cesarean scar and all intrauterine abnormal fibrous tissues, using a glide myometrial flap, and intramyometrial injection of autologous platelet-rich plasma. Qualitative variables were determined, and descriptive statistics were employed to analyze the data in absolute frequencies or percentages. The data obtained were processed using the InfostatTM statistic program.

RESULTS

Following the repair, all women experienced normal menstrual cycles and demonstrated an adequate lower uterine segment thickness, with no evidence of healing defects. All patients experienced early ambulation and were discharged within 24 h. Uterine hemostasis was achieved at specific points, minimizing the use of electrocautery. The standard duration of the procedure was 60 min (skin-to-skin), and the average bleeding was 80-100 ml. No perioperative complications were recorded. A control T2-weighted MRI was performed six months after surgery. All patients displayed a clean, unobstructed endometrial cavity with a thick anterior wall (Median: 14.98 mm, IQR 13-17). Twelve patients became pregnant again, all delivered by cesarean between 36.1 and 38.0 weeks, with a mean of 37.17 weeks. The thickness of the uterine segment before cesarean ranged between 3 and 7 mm, with a mean of 3.91 mm. No cases of placenta previa, dehiscence, placenta accreta spectrum (PAS), or postpartum hemorrhage were reported.

CONCLUSIONS

The comprehensive repair of recurrent low-large defects offers a holistic solution for addressing recurrent hysterotomy defects. Innovative repair concepts effectively address the wound defect and associated fibrosis, ensuring an appropriate myometrial thickness through a gliding myometrial flap.

Skin repair and infection control in diabetic, obese mice using bioactive laser-activated sealants

Conventional wound approximation devices, including sutures, staples, and glues, are widely used but risk of wound dehiscence, local infection, and scarring can be exacerbated in these approaches, including in diabetic and obese individuals. This study reports the efficacy and quality of tissue repair upon photothermal sealing of full-thickness incisional skin wounds using silk fibroin-based laser-activated sealants (LASEs) containing copper chloride salt (Cu-LASE) or silver nanoprisms (AgNPr-LASE), which absorb and convert near-infrared (NIR) laser energy to heat. LASE application results in rapid and effective skin sealing in healthy, immunodeficient, as well as diabetic and obese mice. Although lower recovery of epidermal structure and function was seen with AgNPr-LASE sealing, likely because of the hyperthermia induced by laser and presence of this material in the wound space, this approach resulted in higher enhancement in recovery of skin biomechanical strength compared to sutures and Cu-LASEs in diabetic, obese mice. Histological and immunohistochemical analyses revealed that AgNPr-LASEs resulted in significantly lower neutrophil migration to the wound compared to Cu-LASEs and sutures, indicating a more muted inflammatory response. Cu-LASEs resulted in local tissue toxicity likely because of effects of copper ions as manifested in the form of a significant epidermal gap and a 'depletion zone', which was a region devoid of viable cells proximal to the wound. Compared to sutures, LASE-mediated sealing, in later stages of healing, resulted in increased angiogenesis and diminished myofibroblast activation, which can be indicative of lower scarring. AgNPr-LASE loaded with vancomycin, an antibiotic drug, significantly lowered methicillin-resistant Staphylococcus aureus (MRSA) load in a pathogen challenge model in diabetic and obese mice and also reduced post-infection inflammation of tissue compared to antibacterial sutures. Taken together, these attributes indicate that AgNPr-LASE demonstrated a more balanced quality of tissue sealing and repair in diabetic and obese mice and can be used for combating local infections, that can result in poor healing in these individuals.

Mechanistic insights into intrauterine adhesions

Intrauterine adhesions (IUA), also known as Asherman's syndrome, arise from damage to the basal layer of the endometrium, frequently caused by intrauterine interventions. This damage leads to nonregenerative healing of endometrium resulting in replacement by fibrous connective tissue, which bring about the adherence of opposing endometrium to render the uterine cavity and/or cervical canal partially or completely obliterated. IUA is a common cause of the refractory uterine infertility. Hysteroscopy is the gold standard for diagnosis of IUA. However, the method of accurately predicting the likelihood of achieving a live birth in the future remains established. Classical treatments have shown limited success, particularly in severe cases. Therefore, utilizing new research methods to deepen the understanding of the pathogenesis of IUA will facilitate the new treatment approaches to be found. In this article we briefly described the advances in the pathogenesis of IUA, with focus on inflammation and parenchymal cellular homeostasis disruption, defects in autophagy and the role of ferroptosis, and we also outlined the progress in IUA therapy.

Critical Analysis of Cytoplasmic Progression of Inflammatory Signaling Suggests Potential Pharmacologic Targets for Wound Healing and Fibrotic Disorders

Successful skin wound healing is dependent on an interplay between epidermal keratinocytes and dermal fibroblasts as they react to local extracellular factors (DAMPs, PAMPs, cytokines, etc.) surveyed from that environment by numerous membrane receptors (e.g., TLRs, cytokine receptors, etc.). In turn, those receptors are the start of a cytoplasmic signaling pathway where balance is key to effective healing and, as needed, cell and matrix regeneration. When directed through NF-κB, these signaling routes lead to transient responses to the benefit of initiating immune cell recruitment, cell replication, local chemokine and cytokine production, and matrix protein synthesis. The converse can also occur, where ongoing canonical NF-κB activation leads to chronic, hyper-responsive states. Here, we assess three key players, TAK1, TNFAIP3, and TNIP1, in cytoplasmic regulation of NF-κB activation, which, because of their distinctive and yet inter-related functions, either promote or limit that activation. Their balanced function is integral to successful wound healing, given their significant control over the expression of inflammation-, fibrosis-, and matrix remodeling-associated genes. Intriguingly, these three proteins have also been emphasized in dysregulated NF-κB signaling central to systemic sclerosis (SSc). Notably, diffuse SSc shares some tissue features similar to an excessive inflammatory/fibrotic wound response without eventual resolution. Taking a cue from certain instances of aberrant wound healing and SSc having some shared aspects, e.g., chronic inflammation and fibrosis, this review looks for the first time, to our knowledge, at what those pathologies might have in common regarding the cytoplasmic progression of NF-κB-mediated signaling. Additionally, while TAK1, TNFAIP3, and TNIP1 are often investigated and reported on individually, we propose them here as three proteins whose consequences of function are very highly interconnected at the signaling focus of NF-κB. We thus highlight the emerging promise for the eventual clinical benefit derived from an improved understanding of these integral signal progression modulators. Depending on the protein, its indirect or direct pharmacological regulation has been reported. Current findings support further intensive studies of these points in NF-κB regulation both for their basic function in healthy cells as well as with the goal of targeting them for translational benefit in multiple cutaneous wound healing situations, whether stemming from acute injury or a dysregulated inflammatory/fibrotic response.

Modeling the profibrotic microenvironment in vitro: Model validation

Establishing the molecular and cellular mechanisms of fibrosis requires the development of validated and reproducible models. The complexity of in vivo models challenges the monitoring of an individual cell fate, in some cases making it impossible. However, the set of factors affecting cells in vitro culture systems differ significantly from in vivo conditions, insufficiently reproducing living systems. Thus, to model profibrotic conditions in vitro, usually the key profibrotic factor, transforming growth factor beta (TGFβ-1) is used as a single factor. TGFβ-1 stimulates the differentiation of fibroblasts into myofibroblasts, the main effector cells promoting the development and progression of fibrosis. However, except for soluble factors, the rigidity and composition of the extracellular matrix (ECM) play a critical role in the differentiation process. To develop the model of more complex profibrotic microenvironment in vitro, we used a combination of factors: decellularized ECM synthesized by human dermal fibroblasts in the presence of ascorbic acid if cultured as cell sheets and recombinant TGFβ-1 as a supplement. When culturing human mesenchymal stromal cells derived from adipose tissue (MSCs) under described conditions, we observed differentiation of MSCs into myofibroblasts due to increased number of cells with stress fibrils with alpha-smooth muscle actin (αSMA), and increased expression of myofibroblast marker genes such as collagen I, EDA-fibronectin and αSMA. Importantly, secretome of MSCs changed in these profibrotic microenvironment: the secretion of the profibrotic proteins SPARC and fibulin-2 increased, while the secretion of the antifibrotic hepatocyte growth factor (HGF) decreased. Analysis of transciptomic pattern of regulatory microRNAs in MSCs revealed 49 miRNAs with increased expression and 3 miRNAs with decreased expression under profibrotic stimuli. Bioinformatics analysis confirmed that at least 184 gene targets of the differently expressed miRNAs genes were associated with fibrosis. To further validate the developed model of profibrotic microenvironment, we cultured human dermal fibroblasts in these conditions and observed increased expression of fibroblast activation protein (FAPa) after 12 h of cultivation as well as increased level of αSMA and higher number of αSMA + stress fibrils after 72 h. The data obtained allow us to conclude that the conditions formed by the combination of profibrotic ECM and TGFβ-1 provide a complex profibrotic microenvironment in vitro. Thus, this model can be applicable in studying the mechanism of fibrosis development, as well as for the development of antifibrotic therapy.

Vascular Extracellular Matrix in Atherosclerosis

The extracellular matrix (ECM) plays a central role in the structural integrity and functionality of the cardiovascular system. Moreover, the ECM is involved in atherosclerotic plaque formation and stability. In fact, ECM remodeling affects plaque stability, cellular migration, and inflammatory responses. Collagens, fibronectin, laminin, elastin, and proteoglycans are crucial proteins during atherosclerosis development. This dynamic remodeling is driven by proteolytic enzymes such as matrix metalloproteinases (MMPs), cathepsins, and serine proteases. Exploring and investigating ECM dynamics is an important step to designing innovative therapeutic strategies targeting ECM remodeling mechanisms, thus offering significant advantages in the management of cardiovascular diseases. This review illustrates the structure and role of vascular ECM, presenting a new perspective on ECM remodeling and its potential as a therapeutic target in atherosclerosis treatments.

HOXC10 promotes hypertrophic scar fibroblast fibrosis through the regulation of STMN2 and the TGF-β/Smad signaling pathway

The pathophysiology of hypertrophic scar (HS) shares similarities with cancer. HOXC10, a gene significantly involved in cancer development, exhibits higher expression levels in HS than in normal skin (NS), suggesting its potential role in HS regulation. And the precise functions and mechanisms by which HOXC10 influences HS require further clarification. Gene and protein expressions were analyzed using raeal-time quantitative polymerase chain reaction (RT-qPCR) and western blot techniques. Cell proliferation and migration were evaluated using EdU proliferation assays, CCK-8 assays, scratch assays, and Transwell assays. Chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays were conducted to investigate the interactions between HOXC10 and STMN2. HOXC10 and STMN2 expression levels were significantly higher in HS tissues compared with NS tissues. Silencing HOXC10 led to decreased activation, proliferation, migration, and fibrosis in hypertrophic scar fibroblasts (HSFs). Our findings also indicate that HOXC10 directly targets STMN2. The promotional effects of HOXC10 knockdown on HSF activation, proliferation, migration, and fibrosis were reversed by STMN2 overexpression. We further demonstrated that HOXC10 regulates HSF activity through the TGF-β/Smad signaling pathway. HOXC10 induces the activation and fibrosis of HSFs by promoting the transcriptional activation of STMN2 and engaging the TGF-β/Smad signaling pathway. This study suggests that HOXC10 could be a promising target for developing treatments for HS.

Natural Biological Solutions for Chronic Pathological Problems

Naturally sourced biomolecules and their derivatives have had significant historical impacts in terms of their biomedical application [...].

Effects of lactobacillus pentosus postbiotics on fibrotic response in arecoline-induced oral fibrogenesis

Background/purpose

Oral submucous fibrosis (OSF), characterized by excessive collagen deposition by myofibroblasts, is often linked to Areca nuts consumption. Probiotics consumption has shown protective effects against fibrotic diseases, and recently, their metabolic byproducts, known as postbiotics, have demonstrated superior advantages over probiotics. However, studies on the therapeutic impact of postbiotics on OSF have been scarce. Therefore, this study aims to examine the effect of PostBio GK4, a postbiotic derived from Lactobacillus pentosus GK4, on OSF and explore its underlying mechanisms.

Materials and methods

The cytotoxicity of GK4 in normal buccal mucosal fibroblasts (BMFs) and fibrotic BMFs (fBMFs) were assessed. Following this, we evaluated the effects of GK4 on collagen contraction, migratory, and wound healing capacities in arecoline-induced fibrotic BMFs. Next, Western blotting and ELISA were employed to assess GK4's impact on fibrosis-related proteins such as COL1A1, and α-SMA, as well as on TGF-β and Smad2/3 signaling pathway.

Results

Arecoline was shown to stimulate cell migratory, contractile and wound healing abilities as well as the expression of α-SMA and COL1A1 in BMFs. Treatment with GK4 reduced all arecoline-induced phenomena in BMFs. Moreover, GK4 diminished the increased expression of TGF-β and Smad2/3.

Conclusion

Our findings proposed that GK4 may exert a suppressive effect on arecoline-induced myofibroblast activities via the inhibition of TGF-β and Smad2/3 signaling pathway. Therefore, GK4 holds promise as an adjunct therapeutic approach for intervening in OSF. Further in-vivo and clinical studies are warranted to validate these observations.

New Insights into the Pleiotropic Actions of Dipeptidyl Peptidase-4 Inhibitors Beyond Glycaemic Control

Dipeptidyl peptidase-4 (DPP-4) is a multifunctional serine ectopeptidase that cleaves and modifies a plethora of substrates, including regulatory peptides, cytokines and chemokines. DPP-4 is implicated in the regulation of immune response, viral entry, cellular adhesion, metastasis and chemotaxis. Regarding its numerous substrates and extensive expression inside the body, multitasking DPP-4 has been assumed to participate in different pathophysiological mechanisms. DPP-4 inhibitors or gliptins are increasingly used for the treatment of type 2 diabetes mellitus. Several reports from experimental and clinical studies have clarified that DPP-4 inhibitors exert many beneficial pleiotropic effects beyond glycaemic control, which are mediated by anti-inflammatory, anti-oxidant, anti-fibrotic and anti-apoptotic actions. The present review will highlight the most recent findings in the literature about these pleiotropic effects and the potential mechanisms underlying these benefits, with a specific focus on the potential effectiveness of DPP-4 inhibitors in coronavirus disease-19 and diabetic kidney disease.

CD9 promotes TβR2-TβR1 association driving the transition of human dermal fibroblasts to myofibroblast under hypoxia

BACKGROUND

During wound healing, fibroblast to myofibroblast transition is required for wound contraction and remodeling. While hypoxia is an important biophysical factor in wound microenvironment, the exact regulatory mechanism underlying hypoxia and fibroblast-to-myofibroblast transition remains unclear. We previously found that tetraspanin CD9 plays an important role in oxygen sensing and wound healing. Herein, we investigated the effects of physiological hypoxia on fibroblast-to-myofibroblast transition and the biological function and mechanism of CD9 in it.

METHODS

Human skin fibroblasts (HSF) and mouse dermis wounds model were established under physiological hypoxia (2% O2). The cell viability and contractility of HSF under hypoxia were evaluated by CCK8 and collagen gel retraction, respectively. The expression and distribution of fibroblast-to-myofibroblast transition markers and CD9 in HSF were detected by Western blotting and immunofluorescence. CD9 slicing and overexpressing HSFs were constructed to determine the role of CD9 by small interfering RNA and recombinant adenovirus vector. The association of TβR2 and TβR1 was measured by immunoprecipitation to explore the regulatory mechanism. Additionally, further validation was conducted on mouse dermis wounds model through histological analysis.

RESULTS

Enhanced fibroblast-to-myofibroblast transition and upregulated CD9 expression was observed under hypoxia in vitro and in vivo. Besides, reversal of fibroblast-to-myofibroblast transition under hypoxia was observed when silencing CD9, suggesting that CD9 played a key role in this hypoxia-induced transition. Moreover, hypoxia increased fibroblast-to-myofibroblast transition by activating TGF-β1/Smad2/3 signaling, especially increased interaction of TβR2 and TβR1. Ultimately, CD9 was determined to directly affect TβR1-TβR2 association in hypoxic fibroblast.

CONCLUSION

Collectively, these findings suggest that CD9 promotes TβR2-TβR1 association, thus driving the transition of human dermal fibroblasts to myofibroblast under hypoxia.

Wound Healing and Acute Dermal Toxicity Studies of Ludwigia octovalvis (Jacq.) P. H. Raven (Onagraceae) in Sprague-Dawley Rats

Introduction

The aerial part of Ludwigia octovalvis has been used traditionally in some parts of Asia for the management of wounds owing to the presence of phytochemicals such as tannins, flavonoids, and triterpenoids among others. The incidence of wounds, their associated complications, and the cost of wound care are on the increase globally, therefore, the need to develop alternative wound care agents. The aim of this study was to scientifically investigate the wound healing potential of the ethanolic extract of L. octovalvis using the excision wound healing model in rats and also carry out an acute dermal toxicity investigation of the plant extract.

Method

A 70% ethanol extract of L. octovalvis was prepared for the wound healing activity using the excision wound healing model in Sprague-Dawley rats. Aqueous creams (1, 3, and 10%) were prepared and topically applied to the wounds once daily according to the groups of animals. The wounds were assessed for rates of wound closure on days 3, 5, 7, 9, and 11. Re-epithelialization periods were also determined. Sections of wound tissues obtained on day 13 were subjected to histological investigations. An acute dermal toxicity of the plant extract was investigated.

Results

L. octovalvis treatment (1, 3, and 10%) exhibited a mean percentage wound contraction range of 85.36 ± 7.22-94.14 ± 2.23 on day 11. The extract exhibited re-epithelialization periods of 17.3 ± 1.2, 19.8 ± 2.6, and 16.0 ± 1.7 days for the 1, 3, and 10% extract creams, respectively, whereas the cream-only and 1% silver sulfadiazine treatments resulted in a re-epithelialization period of greater than 28 days. Histopathological investigation revealed enhanced fibroblast infiltration and collagen deposition in the treatment groups. No adverse reaction was observed in the acute dermal toxicity study.

Conclusions

Extract of L. octovalvis exhibited wound healing by enhancing wound contraction, re-epithelialization, fibroblast infiltration, and collagen deposition at the wound site. The extract did not exhibit any toxic reaction in the acute dermal toxicity study.

Effect of Placental Derived Nucleoproteins on liver regeneration in DEN-induced liver fibrosis model

BACKGROUND

Placental Derived Nucleoproteins (PDNs) is commonly associated with the process of angiogenesis, and doesn't affect the healthy vasculature. PDNs are clinically estimated for the treatment of cancer cases and severe hepatic injuries. Thus, the pathophysiological effects of PDNs targeting liver fibrosis is a concern.

OBJECTIVES

To assess the molecular, histopathological, and chemical impact of PDNs on liver regeneration in Diethylnitrosamine (DEN)-induced mice liver fibrosis.

METHODS

Normal untreated reference group of ten mice and two groups of induced liver cirrhosis using the recommended weekly dose of Diethylnitrosamine in total of eleven doses, initially 20 mg/kg body weight, and then 30 mg/kg in the third week, followed by 50 mg/kg for the last eight weeks, one of them combined treatment aligned with injection with total dose of extracted PDNs 25 mg/kg, in comparison to PDNs only treated group. An autopsy was performed after 22 weeks of the initial dose of DEN in each group. Molecular characterization of Alpha smooth muscle actin, TGFβ and NF-κB biomarkers for liver then liver function panel were analyzed and finally hepatopathological changes were observed using H&E stain and Sirius red stain.

RESULTS

Liver enzymes, total bilirubin and total proteins in tissue in PDNs-DEN treated models were controlled in the direction of normal group and 50 % reduction of fibrosis in comparing to DEN-treated models. The cellular arrangement of fibrosis in the DEN entire groups were differentiated with high significant impact on the survival of mice. Increased levels of the biochemical markers in liver homogenate, loss of tissue architecture, and proliferation were observed in induced groups and down regulation of alpha smooth muscle actin, TGFβ and NF-κB.

CONCLUSION

This finding demonstrates an improvement of Liver tissue induced fibrosis using DEN combined with PDNs. This strategy is to generate an animal model with a lower occurrence of fibrosis in a short time treatment regarding liver regeneration.

Unveiling the Therapeutic Potential of Systemic Ozone on Skin Wound Repair: Clinical, Histological, and Immunohistochemical Study in Rats

This study sought to examine the effects of systemic ozone (O3) treatment on the healing of skin wounds induced on the dorsal surface of Wistar rats. The skin wounds were created using a 10 mm round punch following the sagittal medial plane in 72 rats. Then, the animals were randomly assigned to four groups, each receiving the following treatments: group C, which did not undergo treatment with the O3/O2 mixture; group OZ0.3, administered the O3/O2 mixture at a dose of 0.3 mg/kg; group OZ0.7, given the O3/O2 mixture at a dose of 0.7 mg/kg; and group OZ1.0, provided with the O3/O2 mixture at a dose of 1.0 mg/kg. Six animals from each group were euthanized at 7, 14, and 21 days postoperatively. Clinical, histological, histometric, and immunohistochemical (IHC) analyses were accomplished. Data from clinical and histometric assessments revealed that OZ0.7 and OZ1.0 demonstrated more favorable healing, with greater wound contraction observed in the OZ1.0 group at 14 and 21 days. Histologically, the OZ1.0 group exhibited aspects consistent with an accelerated tissue repair process. IHC analysis revealed greater vascular endothelial growth factor (VEGF) immunostaining in the OZ0.7 (7 days) and OZ1.0 (7 and 14 days) groups compared to the C group. Expression of transforming growth factor beta-1 was significantly increased in the OZ0.7 (14 days) and OZ1.0 (7 and 14 days) groups compared to the C group. In conclusion, our data suggest that systemic use of O3 enhanced tissue repair in cutaneous wounds in a dose-dependent manner, with concentrations of 1.0 mg/kg providing the most beneficial effects. Furthermore, the results of this study implicate the use of O3 for the treatment of skin wounds aiming at improving the healing process over time. Our findings suggest the use of O3 as a viable alternative to enhance wound healing and repair.

Energy level as a theranostic factor for successful therapy of tissue injuries with polyphosphate: the triad metabolic energy - mechanical energy - heat

Rationale: Tissue regeneration of skin and bone is an energy-intensive, ATP-consuming process that, if impaired, can lead to the development of chronic clinical pictures. ATP levels in the extracellular space including the exudate of wounds, especially chronic wounds, are low. This deficiency can be compensated by inorganic polyphosphate (polyP) supplied via the blood platelets to the regenerating site. Methods: The contribution of the different forms of energy derived from polyP (metabolic energy, mechanical energy and heat) to regeneration processes was dissected and studied both in vitro and in patients. ATP is generated metabolically during the enzymatic cleavage of the energy-rich anhydride bonds between the phosphate units of polyP, involving the two enzymes alkaline phosphatase (ALP) and adenylate kinase (ADK). Exogenous polyP was administered after incorporation into compressed collagen or hydrogel wound coverages to evaluate its regenerative activity for chronic wound healing. Results: In a proof-of-concept study, fast healing of chronic wounds was achieved with the embedded polyP, supporting the crucial regeneration-promoting activity of ATP. In the presence of Ca2+ in the wound exudate, polyP undergoes a coacervation process leading to a conversion of fibroblasts into myofibroblasts, a crucial step supporting cell migration during regenerative tissue repair. During coacervation, a switch from an endothermic to an exothermic, heat-generating process occurs, reflecting a shift from an entropically- to an enthalpically-driven thermodynamic reaction. In addition, mechanical forces cause the appearance of turbulent flows and vortices during liquid-liquid phase separation. These mechanical forces orient the cellular and mineralic (hydroxyapatite crystallite) components, as shown using mineralizing SaOS-2 cells as a model. Conclusion: Here we introduce the energetic triad: metabolic energy (ATP), thermal energy and mechanical energy as a novel theranostic biomarker, which contributes essentially to a successful application of polyP for regeneration processes.

The Loss of PPARγ Expression and Signaling Is a Key Feature of Cutaneous Actinic Disease and Squamous Cell Carcinoma: Association with Tumor Stromal Inflammation

Given the importance of peroxisome proliferator-activated receptor (PPAR)-gamma in epidermal inflammation and carcinogenesis, we analyzed the transcriptomic changes observed in epidermal PPARγ-deficient mice (Pparg-/-epi). A gene set enrichment analysis revealed a close association with epithelial malignancy, inflammatory cell chemotaxis, and cell survival. Single-cell sequencing of Pparg-/-epi mice verified changes to the stromal compartment, including increased inflammatory cell infiltrates, particularly neutrophils, and an increase in fibroblasts expressing myofibroblast marker genes. A comparison of transcriptomic data from Pparg-/-epi and publicly available human and/or mouse actinic keratoses (AKs) and cutaneous squamous cell carcinomas (SCCs) revealed a strong correlation between the datasets. Importantly, PPAR signaling was the top common inhibited canonical pathway in AKs and SCCs. Both AKs and SCCs also had significantly reduced PPARG expression and PPARγ activity z-scores. Smaller reductions in PPARA expression and PPARα activity and increased PPARD expression but reduced PPARδ activation were also observed. Reduced PPAR activity was also associated with reduced PPARα/RXRα activity, while LPS/IL1-mediated inhibition of RXR activity was significantly activated in the tumor datasets. Notably, these changes were not observed in normal sun-exposed skin relative to non-exposed skin. Finally, Ppara and Pparg were heavily expressed in sebocytes, while Ppard was highly expressed in myofibroblasts, suggesting that PPARδ has a role in myofibroblast differentiation. In conclusion, these data provide strong evidence that PPARγ and possibly PPARα represent key tumor suppressors by acting as master inhibitors of the inflammatory changes found in AKs and SCCs.

Depleting profibrotic macrophages using bioactivated in vivo assembly peptides ameliorates kidney fibrosis

Managing renal fibrosis is challenging owing to the complex cell signaling redundancy in diseased kidneys. Renal fibrosis involves an immune response dominated by macrophages, which activates myofibroblasts in fibrotic niches. However, macrophages exhibit high heterogeneity, hindering their potential as therapeutic cell targets. Herein, we aimed to eliminate specific macrophage subsets that drive the profibrotic immune response in the kidney both temporally and spatially. We identified the major profibrotic macrophage subset (Fn1+Spp1+Arg1+) in the kidney and then constructed a 12-mer glycopeptide that was designated as bioactivated in vivo assembly PK (BIVA-PK) to deplete these cells. BIVA-PK specifically binds to and is internalized by profibrotic macrophages. By inducing macrophage cell death, BIVA-PK reshaped the renal microenvironment and suppressed profibrotic immune responses. The robust efficacy of BIVA-PK in ameliorating renal fibrosis and preserving kidney function highlights the value of targeting macrophage subsets as a potential therapy for patients with CKD.

Spatial regulation of substrate adhesion directs fibroblast morphotype and phenotype

The switching of the fibroblast phenotype to myofibroblast is a hallmark of a wide variety of tissue pathologies. This phenotypical switch is known to be influenced not only by humoral factors such as TGF-β, but also by mechanical and physical cues in the cellular environment, and is accompanied by distinctive changes in cell morphology. However, the causative link between these cues, the concomitant morphological changes, and the resulting phenotypic switch remain elusive. Here, we use protein micropatterning to spatially control dermal fibroblast adhesion without invoking exogenous mechanical changes and demonstrate that varying the spatial configuration of focal adhesions (FAs) is sufficient to direct fibroblast phenotype. We further developed an automated morphometry analysis pipeline, which revealed FA eccentricity as the primary determinant of cell-state positioning along the spectrum of fibroblast phenotype. Moreover, linear fibronectin patterns that constrain the FAs were found to promote a further phenotype transition, characterized by dispersed expression of alpha-smooth muscle actin, pointing to an interesting possibility of controlling fibroblast phenotype beyond the canonical fibroblast-myofibroblast axis. Together, our study reveals that the spatial configuration of adhesion to the cellular microenvironment is a key factor governing fibroblast morphotype and phenotype, shedding new light on fibroblast phenotype regulation.

Adverse cardiac events of hypercholesterolemia are enhanced by sitagliptin in sprague dawley rats

BACKGROUND

Cardiovascular disease (CVD) affects millions worldwide and is the leading cause of death among non-communicable diseases. Western diets typically comprise of meat and dairy products, both of which are rich in cholesterol (Cho) and methionine (Met), two well-known compounds with atherogenic capabilities. Despite their individual effects, literature on a dietary combination of the two in the context of CVD are limited. Therefore, studies on the combined effects of Cho and Met were carried out using male Sprague Dawley rats. An additional interest was to investigate the cardioprotective potential of sitagliptin, an anti-type 2 diabetic drug. We hypothesized that feeding a dietary combination of Cho and Met would result in adverse cardiac effects and would be attenuated upon administration of sitagliptin.

METHODS

Adult male Sprague-Dawley rats were fed either a control (Con), high Met (1.5%), high Cho (2.0%), or high Met (1.5%) + high Cho (2.0%) diet for 35 days. They were orally gavaged with an aqueous preparation of sitagliptin (100 mg/kg/d) or vehicle (water) from day 10 through 35. On day 36, rats were euthanized, and tissues were collected for analysis.

RESULTS

Histopathological evaluation revealed a reduction in myocardial striations and increased collagen deposition in hypercholesterolemia (HChol), responses that became exacerbated upon sitagliptin administration. Cardiac pro-inflammatory and pro-fibrotic responses were adversely impacted in similar fashion. The addition of Met to Cho (MC) attenuated all adverse structural and biochemical responses, with or without sitagliptin.

CONCLUSIONS

Adverse cardiac outcomes in HChol were enhanced by the administration of sitagliptin, and such effects were alleviated by Met. Our findings could be significant for understanding or revisiting the risk-benefit evaluation of sitagliptin in type 2 diabetics, and especially those who are known to consume atherogenic diets.

Blockade of Sialylation with Decrease in Polysialic Acid Levels Counteracts Transforming Growth Factor β1-Induced Skin Fibroblast-to-Myofibroblast Transition

Aberrant sialylation with overexpression of the homopolymeric glycan polysialic acid (polySia) was recently reported in fibroblasts from fibrotic skin lesions. Yet, whether such a rise in polySia levels or sialylation in general may be functionally implicated in profibrotic activation of fibroblasts and their transition to myofibroblasts remains unknown. Therefore, we herein explored whether inhibition of sialylation could interfere with the process of skin fibroblast-to-myofibroblast transition induced by the master profibrotic mediator transforming growth factor β1 (TGFβ1). Adult human skin fibroblasts were pretreated with the competitive pan-sialyltransferase inhibitor 3-Fax-peracetyl-Neu5Ac (3-Fax) before stimulation with recombinant human TGFβ1, and then analyzed for polySia expression, cell viability, proliferation, migratory ability, and acquisition of myofibroblast-like morphofunctional features. Skin fibroblast stimulation with TGFβ1 resulted in overexpression of polySia, which was effectively blunted by 3-Fax pre-administration. Pretreatment with 3-Fax efficiently lessened TGFβ1-induced skin fibroblast proliferation, migration, changes in cell morphology, and phenotypic and functional differentiation into myofibroblasts, as testified by a significant reduction in FAP, ACTA2, COL1A1, COL1A2, and FN1 gene expression, and α-smooth muscle actin, N-cadherin, COL1A1, and FN-EDA protein levels, as well as a reduced contractile capability. Moreover, skin fibroblasts pre-administered with 3-Fax displayed a significant decrease in Smad3-dependent canonical TGFβ1 signaling. Collectively, our in vitro findings demonstrate for the first time that aberrant sialylation with increased polySia levels has a functional role in skin fibroblast-to-myofibroblast transition and suggest that competitive sialyltransferase inhibition might offer new therapeutic opportunities against skin fibrosis.

Ferrostatin-1 inhibits fibroblast fibrosis in keloid by inhibiting ferroptosis

Background

Keloid is a chronic proliferative fibrotic disease caused by abnormal fibroblasts proliferation and excessive extracellular matrix (ECM) production. Numerous fibrotic disorders are significantly influenced by ferroptosis, and targeting ferroptosis can effectively mitigate fibrosis development. This study aimed to investigate the role and mechanism of ferroptosis in keloid development.

Methods

Keloid tissues from keloid patients and normal skin tissues from healthy controls were collected. Iron content, lipid peroxidation (LPO) level, and the mRNA and protein expression of ferroptosis-related genes including solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), transferrin receptor (TFRC), and nuclear factor erythroid 2-related factor 2 (Nrf2) were determined. Mitochondrial morphology was observed using transmission electron microscopy (TEM). Keloid fibroblasts (KFs) were isolated from keloid tissues, and treated with ferroptosis inhibitor ferrostatin-1 (fer-1) or ferroptosis activator erastin. Iron content, ferroptosis-related marker levels, LPO level, mitochondrial membrane potential, ATP content, and mitochondrial morphology in KFs were detected. Furthermore, the protein levels of α-smooth muscle actin (α-SMA), collagen I, and collagen III were measured to investigate whether ferroptosis affect fibrosis in KFs.

Results

We found that iron content and LPO level were substantially elevated in keloid tissues and KFs. SLC7A11, GPX4, and Nrf2 were downregulated and TFRC was upregulated in keloid tissues and KFs. Mitochondria in keloid tissues and KFs exhibited ferroptosis-related pathology. Fer-1 treatment reduced iron content, restrained ferroptosis and mitochondrial dysfunction in KFs, Moreover, ferrostatin-1 restrained the protein expression of α-SMA, collagen I, and collagen III in KFs. Whereas erastin treatment showed the opposite results.

Conclusion

Ferroptosis exists in keloid. Ferrostatin-1 restrained ECM deposition and fibrosis in keloid through inhibiting ferroptosis, and erastin induced ECM deposition and fibrosis through intensifying ferroptosis.

Inhibition and reversal of a TGF-β1 induced myofibroblast phenotype by adipose tissue-derived paracrine factors

BACKGROUND

Hypertrophic scarring results from myofibroblast differentiation and persistence during wound healing. Currently no effective treatment for hypertrophic scarring exists however, autologous fat grafting has been shown to improve scar elasticity, appearance, and function. The aim of this study was to understand how paracrine factors from adipose tissues and adipose-derived stromal cells (ADSC) affect fibroblast to myofibroblast differentiation.

METHODS

The transforming growth factor-β1 (TGF-β1) induced model of myofibroblast differentiation was used to test the effect of conditioned media from adipose tissue, ADSC or lipid on the proportion of fibroblasts and myofibroblasts.

RESULTS

Adipose tissue conditioned media inhibited the differentiation of fibroblasts to myofibroblasts but this inhibition was not observed following treatment with ADSC or lipid conditioned media. Hepatocyte growth factor (HGF) was readily detected in the conditioned medium from adipose tissue but not ADSC. Cells treated with HGF, or fortinib to block HGF, demonstrated that HGF was not responsible for the inhibition of myofibroblast differentiation. Conditioned media from adipose tissue was shown to reduce the proportion of myofibroblasts when added to fibroblasts previously treated with TGF-β1, however, conditioned media treatment was unable to significantly reduce the proportion of myofibroblasts in cell populations isolated from scar tissue.

CONCLUSIONS

Cultured ADSC or adipocytes have been the focus of most studies, however, this work highlights the importance of considering whole adipose tissue to further our understanding of fat grafting. This study supports the use of autologous fat grafts for scar treatment and highlights the need for further investigation to determine the mechanism.