BTBD8 contributes to the pathogenesis of inflammatory bowel disease through regulating intestinal barrier integrity and inflammation. However, its role in idiopathic pulmonary fibrosis (IPF) remains unknown. Here we investigated whether BTBD8 plays a role in bleomycin-induced pulmonary fibrosis. Pulmonary fibrosis was induced in wild-type (WT) and Btbd8 knockout (KO) mice by intratracheal instillation of bleomycin. The mice were sacrificed on day 7 or 12. Subsequently, the progression of bleomycin-induced pulmonary fibrosis was assessed. We found that Btbd8 KO mice are more susceptible to bleomycin-induced pulmonary fibrosis, with more severe body weight loss and pulmonary injury, increased collagen deposition and myofibroblast accumulation. We further demonstrated that BTBD8 functions in pulmonary fibroblasts to suppress the conversion of fibroblasts to myofibroblasts. Moreover, Btbd8 deficiency promotes the infiltration of inflammatory cells and the secretion of pro-inflammatory cytokines in IPF mouse model. These results highlight the critical role of BTBD8 in the pathogenesis of bleomycin-induced pulmonary fibrosis in mice, and suggest that BTBD8 may alleviate bleomycin-induced fibrosis by suppressing the differentiation of fibroblasts to myofibroblast, as well as inflammatory responses.

Biological processes are often spatially regulated, ensuring molecular and cellular events occur in their most strategically advantageous locations. Cellular senescence, marked by cell cycle arrest and hypersecretion, is recognized as an important part of physiological processes like development and healing, but it also contributes to aging and disease. However, the spatial distribution of senescent cells and its physiological and pathological impact remain unclear. Here we compile evidence on senescent cell localization in development, healing, and aging. We emphasize the significance of their spatial patterns and speculate on the effects of disrupted spatial positioning of senescence in relation to pathologies. To summarize the specific spatial functions of senescent cells, we propose to refer to them as 'barrier' and 'conductor' functions. The 'barrier' function of senescent cells, due to their altered morphology and apoptosis resistance, separates tissues and builds a border between two environments. The conductor function, with the secretion of signaling factors, influences the surrounding area and stimulates migration, differentiation, or proliferation, among other processes. Overall, this Review explores the spatial patterning of cellular senescence in biological processes, highlighting its dual roles as 'barrier' and 'conductor' functions, and examines the implications of senescent cell distribution in development, healing, aging, and disease.

An expander capsule is a fibrous membrane that forms around a tissue expander. However, its outcome is still unclear. Here we investigated the biomechanical and histological outcomes of cervical capsules that were left in vivo after expanders were removed.

The deep and superficial capsules of 29 human cervical expanders were collected to serve as an experimental group. All 29 patients sustained facial and neck burn scars and underwent scar excision and expanded skin flap transfer. These capsules were divided into four groups based on the in vivo persistence time of the capsules following expander removal. The control group featured skin from five normal subjects. We investigated the biomechanics and histology of each group of capsules.

Capsule thickness, Young's modulus, collagen content, type I/III collagen ratio and α-SMA expression level were significantly related to the layer and the persistence time of the capsule in vivo (p＜0.05). Capsules persisted for more than 24 months following expander removal, the Young's modulus of the capsules remained greater than that of normal skin, limiting neck mobility. Moreover, some patients experience cord-like capsular contracture and a cervical pulling sensation, which may be attributable to the fusion of the deep expander capsules and platysma muscle.

Following the removal of neck expanders, the capsules can persist in vivo for a long time, affecting cervical contours and mobility.

This study presents a transcriptomic analysis of the cingulate cortex (CING) in Parkinson's disease (PD) and Parkinson's disease dementia (PDD) using a High-efficiency single-nucleus RNA sequencing (HiF-snRNA-seq) protocol optimized for post-mortem brain samples. RNA quality prediction, poly-A tailing, and dCas9-targeted depletion enabled analysis of 77 high-quality samples from 240 cases, yielding over 2 million nuclei classified into seven major cell types. Disease conditions revealed altered astrocyte and microglia proportions, implicating their roles in neuroinflammation. Differential expression analysis identified unique and shared genes across PD and PDD, linked to synaptic remodeling, stress responses, and inflammation. Stage-specific analysis uncovered tau-dependent early-stage genes and inflammation-associated late-stage genes. This study highlights the CING's central role in PD and PDD pathophysiology, offering insights into disease mechanisms and identifying candidate genes and pathways for therapeutic and biomarker development.

Periodontitis is one of the major oral health issues worldwide, with significant impacts on oral health and patients's quality of life, but current therapies have not achieved optimal regeneration of periodontal tissue. This study developed scaffolds using natural tussah silk fibroin (TSF) cross-linked with regenerated silk fibroin (SF) nanofibers to improve mechanical properties and wet-state stability. Zinc oxide (ZnO) and polydopamine (PDA) composite nanoparticles were loaded into scaffold to impart its antibacterial and photothermal properties to construct a photo-responsive composite scaffold (ZnO/PDA/TSF-SF). After characterization, ZnO/PDA/TSF-SF demonstrated excellent antibacterial ability, biocompatibility, and photothermal stability. In vitro cell evaluations under 635 nm red light irradiation-mediated photo-biomodulation (PBM) demonstrated that ZnO/PDA/TSF-SF promoted fibroblast proliferation and enhanced expression of proteins and genes associated with tissue repair, such as collagen I (Col I), fibronectin (FN), and alpha smooth muscle actin (α-SMA). A rat model of periodontitis developed for evaluations of antibacterial and tissue repair effects showed that ZnO/PDA/TSF-SF improved alveolar bone and reversed bone loss. ZnO/PDA/TSF-SF improved inflammation significantly through reduction in tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), and IL-6 levels in serum and gingival tissues of modeled rats. Also, the scaffold markedly increased levels of anti-inflammatory cytokine interleukin-10 (IL-10) and elevated protein and mRNA expression levels of tissue repair-related proteins and endothelial cell markers. ZnO/PDA/TSF-SF scaffold exhibited good biocompatibility, osteogenesis, and photo-responsive antibacterial properties, thereby demonstrating therapeutic potential in treating periodontitis.

This study aimed to investigate the regulatory role of the AMP-activated protein kinase (AMPK)/mechanistic target of rapamycin (mTOR) signaling pathway in mediating transforming growth factor-beta 1 (TGF-β1)-induced cellular proliferation and transdifferentiation processes in human pterygium fibroblasts (HPFs).

HPFs were stimulated with TGF-β1 in vitro. Cell viability was assessed using the CCK-8 assay at 12/24/48-h post-stimulation, while migratory capacity was evaluated through standardized wound healing assays. Quantitative real-time PCR (qPCR) and western blotting analyses were employed to evaluate the expression of proliferation marker proliferating cell nuclear antigen (PCNA) and myofibroblast transdifferentiation biomarker α-smooth muscle actin (α-SMA). Western blotting further characterized the activation status of AMPK/mTOR signaling by quantifying phosphorylated AMPK (p-AMPK) and phosphorylated mTOR (p-mTOR), with total AMPK and mTOR levels serving as loading controls. To establish mechanistic causality, TGF-β1-primed HPFs were modulated using the AMPK inhibitor Compound C and activator AICAR for 24 h. Functional consequences were analyzed through CCK-8 viability assays and wound healing assays, while molecular correlates were assessed via qPCR and western blotting for PCNA, α-SMA, and pathway components. This comprehensive approach delineated the AMPK/mTOR axis as a critical regulator of TGF-β1-driven fibrotic phenotype acquisition in HPFs.

Following TGF-β1 pretreatment-induced activation of human HPFs, both cell viability and migratory capacity were markedly enhanced, with concomitant upregulation of PCNA and α-SMA. Compound C-mediated AMPK inhibition potentiated the TGF-β1-induced enhancements in HPFs viability and migration rate, concomitant with reduced p-AMPK/AMPK ratio and elevated expression of PCNA, α-SMA, and p-mTOR/mTOR ratio. Conversely, AICAR-driven AMPK activation attenuated TGF-β1-stimulated effects, demonstrating diminished viability, suppressed migratory capacity, increased p-AMPK/AMPK ratio, and decreased expression of PCNA, α-SMA, and p-mTOR/mTOR ratio.

This study demonstrates the critical regulatory role of the AMPK/mTOR signaling pathway in controlling TGF-β1-induced proliferation and transdifferentiation in HPFs, thereby providing a potential mechanistic framework for developing novel therapeutic interventions targeting fibrotic ocular surface disorders.

To investigate the roles of oxidative stress-related differentially expressed genes (OSRDEGs) in keloid formation and explore their potential value in diagnosis and treatment.

Gene expression data from the GEO database, including GSE145725 and GSE44270 as training sets and GSE7890 as a validation set, were utilized. OSRDEGs were identified, followed by Weighted Gene Co-expression Network Analysis (WGCNA), GO/KEGG enrichment analysis, and Gene Set Enrichment Analysis (GSEA). Key genes were further screened through protein-protein interaction (PPI) network analysis and receiver operating characteristic (ROC) curve analysis. miRNA targets, transcription factors (TF), and potential drug targets of these genes were predicted. Immune cell infiltration analysis was performed to assess the association between OSRDEGs and immune cells, which was validated using GSE7890. Finally, the expression of key genes was experimentally validated using quantitative PCR (qPCR), immunohistochemistry (IHC), and hematoxylin-eosin (HE) staining.

A total of 13 OSRDEGs were identified. WGCNA and functional enrichment analyses revealed that these genes were primarily involved in fibrosis and inflammatory processes in keloids, such as the MAPK signaling pathway, lymphocyte and monocyte proliferation, and inflammatory pathways involving IL-18 and IL-23. PPI network analysis, ROC analysis, and immune infiltration results identified Endothelin-1 (EDN1) and Neurotrophin-3(NTF3) as key genes with high sensitivity and specificity. These genes were positively and negatively correlated with activated mast cells, respectively, suggesting their dual regulatory roles in fibrosis and inflammation. External dataset validation, qPCR, correlation analysis, HE staining, and IHC results demonstrated that EDN1 and NTF3 were highly expressed in keloid tissues and were associated with excessive collagen deposition and immune cell infiltration.

EDN1 and NTF3, as OSRDEGs, play critical roles in the pathogenesis and progression of keloids. They may contribute to fibrosis and inflammation through the regulation of oxidative stress, the MAPK signaling pathway, and mast cell activation. These findings highlight EDN1 and NTF3 as potential diagnostic biomarkers and therapeutic targets, providing novel insights into the pathogenesis and treatment strategies for keloids.

Dysmobility of the proximal interphalangeal joint (PIPJ) often arises following trauma, inflammation, or surgery, leading to joint stiffness and reduced range of motion. This condition results from capsular shortening and the development of arthrofibrosis, which restricts mobility and contributes to contracture formation.

This study investigates the influence of joint position on capsular space volume distribution in the PIPJ, hypothesizing that the mid-flexion position maximizes capsular space, contributing to ligament shortening and arthrofibrosis. This study investigates the influence of joint position on capsular space volumen distribution in PIPJ, hypothesizing that the mid- flexion position maximizes capsular space, contributing to ligament shortening and arthrofibrosis.

A cadaveric study examining capsuloligamentous dynamics of the PIPJ across various joint positions.

Fifteen fingers from five fresh frozen cadaver specimens were evaluated through three studies: RESULTS: 1. The PIPJ demonstrated close-packed positions at full flexion and extension, with maximum capsular space volume observed in the mid-flexion position (30°-40° flexion). 2. Silicone injection consistently held the joint in a mid-flexion position, indicating maximal capsular volume. 3. Latex distribution varied with joint position, concentrating dorsally in extension, spreading equally volar-dorsal in mid-flexion and shifting volarly in flexion.

We propose call to call the mid-flexion position (of 30º-40º flexion) the "neutral" position. This position maximizes capsular space volume, facilitating ligament shortening and arthrofibrosis. Extension minimizes volar capsularspace volume and may be essential for preventing flexion contractures. Clinically, immobilizing the proximal interphalangeal joint in extension with dorsal compression may help prevent contracture and reduce edema, while manual therapy should target the mid-flexion position to enhance joint mobilization.

Keloid is a dermal fibrotic disorder characterized by excessive extracellular matrix production by fibroblasts. Despite the significance of mechanostimulation in fibrotic diseases, its association with keloid pathophysiology or treatment remains unexplored.

To investigate the role of mechanical force in keloid formation and elucidate the significance of Rho-associated coiled-coil-containing kinase 1 (ROCK1) as a mechanoresponsive target for keloid treatment.

Patient-derived keloid fibroblasts (KFs) were subjected to cyclic stretching ranging from 0% to 20% elongation using a cell-stretching system. We observed the inhibitory effects of the ROCK1 inhibitor Y27632 on KFs and keloid formation. Validation was performed using a keloid xenograft severe combined immune-deficient (SCID) mouse model.

ROCK1 was overexpressed in KFs isolated from patients. Cyclic stretching induced fibroblast proliferation and actin polymerization by activating Rho/ROCK1 signalling. Treatment with Y27632 downregulated fibrotic markers reduced the migration capacity of KFs and induced extensive actin cytoskeleton remodelling. In the keloid xenograft SCID mouse model, Y27632 effectively suppressed keloid formation, mitigating inflammation and fibrosis.

The ROCK1 inhibitor Y27632 is a promising molecule for keloid treatment, exerting its effects through actin cytoskeleton remodelling and nuclear inhibition of fibrotic markers in keloid pathogenesis.

Natural products are known to have distinct roles in the treatment of various diseases. However, the potential role of ginsenoside Rg1 (GRg1) in the context of scald injuries remains unclear. This study aimed to elucidate the effects of GRg1 on scald wound healing by utilizing a mouse scald wound model and administering varying concentrations of GRg1 orally. RNA sequencing (RNA-seq) was employed to identify the signaling pathways and key genes influenced by GRg1 in the wound healing process. Our findings indicate that mice treated with a low concentration of GRg1 exhibited a significantly higher wound healing rate compared with the model group and other treatment groups. Through RNA-seq, we observed that the gene expression profile in the wound tissues of the low-concentration-treated group was consistent with that of the normal control group. Furthermore, a low concentration of GRg1 was found to maintain cellular energy metabolism homeostasis by enhancing mitochondrial aerobic respiration and the tricarboxylic acid cycle. In addition, GRg1 facilitated wound healing by restoring the expression of genes associated with cell migration and adhesion. Confirming the appropriate concentration of GRg1 that accelerates tissue healing at scald sites and enhances our understanding of the efficacy and molecular mechanisms underlying the therapeutic effects of natural products in disease treatment.

Intervertebral disc degeneration (IDD) results from an imbalance between anabolic and catabolic processes in the extracellular matrix (ECM). Due to complex biochemical interactions, a comprehensive understanding is needed. This study presents a regulatory network model (RNM) for nucleus pulposus cells (NPC), representing normal intervertebral disc (IVD) conditions. The RNM includes 33 proteins, and 153 interactions based on literature, incorporating key NPC regulatory mechanisms. A semi-quantitative approach calculates the basal steady state, accurately reflecting normal NPC activity. Model validation through published studies replicated pro-catabolic and pro-anabolic shifts, emphasizing the roles of transforming growth factor beta (TGF-β) and interleukin-1 receptor antagonist (IL-1Ra) in ECM regulation. This IVD RNM is a valuable tool for predicting IDD progression, offering insights into ECM degradation mechanisms and guiding experimental research on IVD health and degeneration.

Hypertrophic scar (HS) is a common fibroproliferative disorders with no fully effective treatments. The conversion of fibroblasts to myofibroblasts is known to play a critical role in HS formation, making it essential to identify molecules that promote myofibroblast dedifferentiation and to elucidate their underlying mechanisms. In this study, we used comparative transcriptomics and single-cell sequencing to identify key molecules and pathways that mediate fibrosis and myofibroblast transdifferentiation. Epidermal stem cell-derived extracellular vesicles (EpiSC-EVs) were isolated via ultracentrifugation and filtration, followed by miRNA sequencing to identify miRNAs targeting key molecules. After in vitro and in vivo treatment with EpiSC-EVs, we assessed antifibrotic effects through scratch assays, collagen contraction assays, Western blotting, and immunofluorescence. Transcriptomic sequencing and rescue experiments were used to investigate the molecular mechanism by which miR-203a-3p in EpiSC-EVs induces myofibroblast dedifferentiation. Our results indicate that PIK3CA is overexpressed in HS tissues and positively correlates with fibrosis. EpiSC-EVs were absorbed by scar-derived fibroblasts, promoting dedifferentiation from myofibroblasts to quiescent fibroblasts. Mechanistically, miR-203a-3p in EpiSC-EVs plays an essential role in inhibiting PIK3CA expression and PI3K/AKT/mTOR pathway hyperactivation, thereby reducing scar formation. In vivo studies confirmed that EpiSC-EVs attenuate excessive scarring through the miR-203a-3p/PIK3CA axis, suggesting EpiSC-EVs as a promising therapeutic approach for HS.

Adenomyosis is characterized by abnormal uterine bleeding, dysmenorrhea and subfertility. Increased expression of angiogenesis markers in adenomyosis presents a treatment opportunity and was studied in an adenomyosis mouse model. Mice were administered tamoxifen (1 mg/kg) on neonatal days 2-5. At six weeks of age, mice received oral treatment with axitinib 3 mg/kg ('dose I/AX3', n = 34), axitinib 25 mg/kg ('dose II/AX25' n = 34), or with vehicle-only ('placebo', n = 34). The prevalence and severity of adenomyosis were assessed. An adenomyosis severity index was calculated by multiplying mean grade/mouse by the percentage affected surface area. Angiogenesis-related gene expression was evaluated using real-time quantitative PCR. 101 mice completed adenomyosis induction and could be analyzed. The prevalence of adenomyosis was 30/33 (90.0%) in dose I, 29/34 (85.3%) in dose II, and 30/34 (88.2%) in placebo treated mice (p = 0.78). High grade (2/3) adenomyosis was significantly less prevalent in mice treated with axitinib dose II (n = 19, 55.9%) than in the placebo group (n = 27, 79.4%, p < 0.05). The adenomyosis severity index was reduced by 48% in the axitinib-treated groups (dose I, p < 0.05). The expression of angiogenic growth factors was reduced in the dose I and II axitinib-treated groups compared to the placebo-treated group. Following these promising first results, further research should focus on commonality among different angiostatic drugs, potential side effects, as well as the method and timing of application.

Ischemic stroke is a major cause of disability in adults. Early treatment with thrombolytics and/or thrombectomy can significantly improve outcomes; however, following these acute interventions, treatment is limited to rehabilitation therapies. Thus, identification of therapeutic strategies that can help restore brain function in the post-acute phase remains a major challenge. Here we report that genetic or pharmacologic inhibition of the PDGF-CC/PDGFRα pathway, which has previously been implicated in stroke pathology, significantly reduced myofibroblast expansion in the border of the fibrotic scar and improved outcome in a sensory-motor integration test after experimental ischemic stroke. This was supported by gene expression analyses of cerebrovascular fragments showing upregulation of profibrotic/proinflammatory genes, including genes of the TGF pathway, after ischemic stroke or intracerebroventricular injection of active PDGF-CC. Further, longitudinal intravital 2-photon imaging revealed that inhibition of PDGFRα dampened the biphasic pattern of stroke-induced vascular leakage and enhanced vascular perfusion in the ischemic lesion. Importantly, we found PDGFRα inhibition to be effective in enhancing functional recovery when initiated 24 hours after ischemic stroke. Our data implicate the PDGF-CC/PDGFRα pathway as a crucial mediator modulating post-stroke pathology and suggest a post-acute treatment opportunity for patients with ischemic stroke targeting myofibroblast expansion to foster long-term CNS repair.

Microfocused ultrasound with real-time visualization (MFU-V) is often used for noninvasive skin lifting, by precisely targeting dermal and subcutaneous tissues to create thermal coagulation points (TCPs). These TCPs denature collagen and initiate a transient inflammatory response, ultimately attracting dermal fibroblasts and inducing efficient neocollagenesis and extracellular matrix (ECM) remodeling, yielding to MFU-V's desired skin-lifting effects. The current study investigates MFU-V's underlying mode of action based on the histological progression of TCPs in the skin, providing new insight into the technology's regenerative effect.

Following standard triple-depth MFU-V treatment, in vivo skin samples were assessed using histology and immunohistochemistry to evaluate TCPs, heat shock protein (HSP47), and elastin expression in fibroblasts.

MFU-V treatment induced elongated, flame-like TCPs with denatured collagen at focal depths of 1.5, 3.0, and 4.5 mm within the skin-each corresponding to its respective transducer depth. Time-dependent progression of TCPs showed significantly increased scores of fibroblasts and mature collagen along with recruitment of HSP47-positive fibroblasts to TCP areas on Day 90. Collagen formation and later maturation were visualized. Newly synthesized elastin significantly increased in the TCP area on Day 90 compared to Day 14.

This work provides histological evidence of stimulation and regeneration of newly synthesized elastin fibers after TCP induction. MFU-V-generated TCPs triggered the body's own healing cascade of collagen denaturation, transient inflammation, proliferation, and tissue remodeling, resulting in attraction of HSP47-positive fibroblasts to the TCP sites, and new collagen and elastin fiber regeneration by fibroblasts. Besides the well-described neocollagenesis, this study demonstrates that MFU-V treatment induces elastin neogenesis that may result not only in skin lifting but also in improved skin elasticity, providing an overall regenerative effect.

Basic fibroblast growth factor (bFGF) is a significant member of the fibroblast growth factor (FGF) family. The bFGF has a three-dimensional structure comprising 12 reverse parallel β-folds. This structure facilitates tissue wound repair, angiogenesis, bone formation, cartilage repair, and nerve regeneration. Consequently, it has garnered significant attention from scholars both domestically and internationally. However, the instability and degradation properties of bFGF in vivo have limited its clinical application. Significant interest has arisen in the development of novel bFGF delivery systems that can address the shortcomings of bFGF and enhance its bioavailability by controlling the release amount, timing, and location. This article offers a comprehensive overview of the research and recent advances in various bFGF delivery systems, including hydrogels, liposomes, microspheres, and nanoparticles. Subsequently, the applications of bFGF pharmaceutical preparations in various fields are described. Finally, the current clinical applications of bFGF drug formulations and those in clinical trials are discussed, along with their clinical translation and future trends.

Tissue repair and reconstruction are a clinical difficulty. Bioelectricity has been identified as a critical factor in supporting tissue and cell viability during the repair process, presenting substantial potential for clinical application. This review delves into various sources of electrical stimulation and identifies appropriate electrode materials for clinical use. It also highlights the biological mechanisms of electrical stimulation at both the subcellular and cellular levels, elucidating how these interactions facilitate the repair and regeneration processes across different organs. Moreover, specific electrode materials and stimulation sources are outlined, detailing their impact on cellular activity. The future development trends are projected from two perspectives: the optimization of equipment performance and the fulfillment of clinical demands, focusing on the feasibility, safety, and cost-effectiveness of technologies.

Mechanical stress and pathological signaling trigger the activation of fibroblasts to myofibroblasts, which impacts extracellular matrix composition, disrupts normal wound healing, and can generate deleterious fibrosis. Myocardial fibrosis independently promotes cardiac arrhythmias, sudden cardiac arrest, and contributes to the severity of heart failure. Fibrosis can also alter cell-to-cell communication and increase myocardial stiffness which eventually may lead to lusitropic and inotropic cardiac dysfunction. Human induced pluripotent stem cell derived cardiac fibroblasts (hiPSC-CFs) have the potential to enhance clinical relevance in precision disease modeling by facilitating the study of patient-specific phenotypes. However, it is unclear whether hiPSC-CFs can be activated to become myofibroblasts akin to primary cells, and the key signaling mechanisms in this process remain unidentified.

We aim to explore the notable changes in fibroblast phenotype upon passage-mediated activation of hiPSC-CFs with increased mitochondrial metabolism, like primary cardiac fibroblasts.

We activated the hiPSC-CFs with serial passaging from passage 0 to 3 (P0 to P3) and treatment of P0 with TGFβ1.

Passage-mediated activation of hiPSC-CFs was associated with a gradual induction of genes to initiate the activation of these cells to myofibroblasts, including collagen, periostin, fibronectin, and collagen fiber processing enzymes with concomitant downregulation of cellular proliferation markers. Most importantly, canonical TGFβ1 and Hippo signaling component genes including TAZ were influenced by passaging hiPSC-CFs. Seahorse assay revealed that passaging and TGFβ1 treatment increased mitochondrial respiration, consistent with fibroblast activation requiring increased energy production, whereas treatment with the glutaminolysis inhibitor BPTES completely attenuated this process.

Our study highlights that the hiPSC-CF passaging enhanced fibroblast activation, activated fibrotic signaling pathways, and enhanced mitochondrial metabolism approximating what has been reported in primary cardiac fibroblasts. Thus, hiPSC-CFs may provide an accurate in vitro preclinical model for the cardiac fibrotic condition, which may facilitate the identification of putative anti-fibrotic therapies, including patient-specific approaches.

Wound healing as a result of a skin injury involves a series of dynamic physiological processes, leading to wound closure, re-epithelialization, and the remodeling of the extracellular matrix (ECM). The primary scar formed by the new ECM never fully regains the original tissue's strength or flexibility. Moreover, in some cases, due to dysregulated fibroblast activity, proliferation, and differentiation, the normal scarring can be replaced by pathological fibrotic tissue, leading to hypertrophic scars or keloids. These disorders can cause significant physical impairment and psychological stress and represent significant challenges in medical management in the wound-healing process. The present study aimed to investigate the therapeutic effects of exogenously applied carbon dioxide (CO2) on fibroblast behavior, focusing on viability, proliferation, migration, and differentiation to myofibroblasts. We found that CO2 exposure for up to 60 min did not significantly affect fibroblast viability, apoptosis rate, or proliferation and migration capacities. However, a notable finding was the significant reduction in α-smooth muscle actin (α-SMA) protein expression, indicative of myofibroblast differentiation inhibition, following CO2 exposure. This effect was specific to CO2 and concentration as well as time-dependent, with longer exposure durations leading to greater reductions in α-SMA expression. Furthermore, the inhibition of myofibroblast differentiation correlated with a statistically significantly reduced glycolytic and mitochondrial energy metabolism, and as a result, with a reduced ATP synthesis rate. This very noticeable decrease in cellular energy levels seemed to be specific to CO2 exposure and could not be observed in the control cultures using nitrogen (N2)-saturated solutions, indicating a unique and hypoxia-independent effect of CO2 on fibroblast metabolism. These findings suggest that exogenously applied CO2 may possess fibroblast differentiation-reducing properties by modulating fibroblast's energy metabolism and could offer new therapeutic options in the prevention of scar and keloid development.

A significant role in the pathogenesis of CAVD is played by innate immunity cells, such as macrophages. In stenotic valves, macrophages have enhanced inflammatory activity, and the population's balance is shifted toward pro-inflammatory ones. Pro-inflammatory macrophages release cytokines, chemokines, and microRNA, which can directly affect the resident valvular cells and cause valve calcification. In CAVD patients, macrophages may have more pronounced pro-inflammatory properties, enhanced not only by paracrine signals but also by juxtacrine Notch signaling and epigenetic factors, which influence the maturation of macrophages' progenitors. In this review, we observe the accumulated data on the involvement of macrophages in CAVD development via paracrine and juxtacrine interactions.

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.

An increasing number of women are undergoing breast implantation for cosmetic purposes or for reconstructive purposes after breast excision. The surface morphology of the breast implant is a key factor associated with the induction of capsule contraction. The effect of surface morphology on the inflammatory response after implant insertion remains unclear, however. The authors conducted comparative analyses to determine the effect of the textured and smooth surface morphology of silicone sheets.

Each type of silicone sheet was inserted into the subcutaneous pocket below the panniculus carnosus in C57BL/6 mice and mice with genetic disruption of CARD9 , Dectin-1 , Dectin-2 , or Mincle . The authors analyzed collagen fiber capsule thickness, histologic findings, and macrophage inflammatory response, including transforming growth factor (TGF)-β synthesis.

The authors found that textured surface morphology contributed to the formation of collagen fiber capsules and the accumulation of fibroblasts and myofibroblasts, and was accompanied by the accumulation of TGF-β-expressing macrophages and foreign-body giant cells. CARD9 deficiency attenuated collagen fiber capsule formation, macrophage responses, and TGF-β synthesis, although the responsible C-type lectin receptors remain to be clarified.

These results suggest that CARD9 may have a strong impact on silicone sheet morphology through the regulation of macrophage responses.

Silicone breast implants have been widely used for postmastectomy and cosmetic augmentation mammaplasty breast reconstruction. The authors sought to elucidate the surface morphology of the breast implant as one of the key factors associated with the formation of collagen fiber capsules.

Therapeutic, V.

An extensive network of cutaneous nerves, neuropeptides, and specific receptors richly innervates the skin and influences a variety of physiological and pathological processes. The sensory and autonomic nerve fibers secrete a variety of neuropeptides that are essential to the different phases of wound healing. In addition to initiating a neurogenic inflammatory response in the early stages of healing, neuropeptides also control wound healing by influencing immune cells, repair cells, and the growth factor network. However, the precise mechanism by which they accomplish these roles in the context of cutaneous wound healing is still unknown. Investigating the mechanisms of action of neuropeptides in wound healing and potential therapeutic applications is therefore urgently necessary. The present review discusses the process of wound healing, types of neuropeptides, potential mechanisms underlying the role of neuropeptides in cutaneous wound healing, as well as some neuropeptide-derived treatment strategies, such as hydrogels, new dressings, electro stimulation, and skin-derived precursors. Future in-depth mechanistic studies of neuropeptides in cutaneous wound healing may provide opportunities to develop therapeutic technologies that harness the roles of neuropeptides in the wound healing process.

Fibroblasts, the principal cellular mediators of connective tissue remodeling, play a crucial role in the formation of physiological and pathological scars. Understanding the intricate interplay between fibroblasts and other cellular and molecular components is essential for elucidating the underlying mechanisms driving scar formation. Hypertrophic scars, keloids and atrophic scars arise from dysregulated wound healing processes characterized by persistent inflammation, aberrant collagen deposition, and impaired extracellular matrix remodeling. Fibroblasts play a central role in the pathogenesis of such pathological scars, driving aberrant extracellular matrix remodeling, subsequently contributing to the formation of raised or depressed fibrotic lesions. The investigation of complex interactions between fibroblasts and the microenvironment is crucial for developing targeted therapeutic interventions aimed at modulating fibroblast activity and improving clinical outcomes in patients with pathological scars. Further research into the molecular pathways governing fibroblast behavior and their heterogeneity holds promise for advancing scar management strategies. This narrative review was performed to shed light on the mechanisms behind scar formation, with a special focus on the role of fibroblasts in the formation of different types of scars, providing insights into the pathophysiology of these conditions. Through the analysis of current knowledge, this review seeks to identify the key cellular and molecular mechanisms involved in fibroblast activation, collagen synthesis, and extracellular matrix remodeling in hypertrophic scar, keloid, or atrophic scar formation.

Heart valve tissue engineering holds the potential to transform the surgical management of congenital heart defects affecting the pediatric pulmonary valve (PV) by offering a viable valve replacement. While aiming to recapitulate the native valve, the minimum requirement for tissue engineered heart valves (TEHVs) has historically been adequate mechanical function at implantation. However, long-term in situ functionality of TEHVs remains elusive, suggesting that a closer approximation of the native valve is required. The realization of biomimetic engineered pediatric PV is impeded by insufficient characterization of healthy pediatric tissue. In this study, we comprehensively characterized the planar biaxial tensile behaviour, extracellular matrix (ECM) composition and organization, and valvular interstitial cell (VIC) phenotypes of PVs from piglets to provide benchmarks for TEHVs. The piglet PV possessed an anisotropic and non-linear tension-strain profile from which material constants for a predictive constitutive model were derived. The ECM of the piglet PV possessed a trilayer organization populated by collagen, glycosaminoglycans, and elastin. Biochemical quantification of ECM content normalized to wet weight and DNA content of PV tissue revealed homogeneous distribution across sampled regions of the leaflet. Finally, VICs in the piglet PV were primarily quiescent vimentin-expressing fibroblasts, with a small proportion of activated α-smooth muscle actin-expressing myofibroblasts. Overall, piglet PV properties were consistent with those reported anecdotally for pediatric human PVs and distinct from those of adult porcine and human PVs, supporting the utility of the properties determined here to inform the design of tissue engineered pediatric PVs. STATEMENT OF SIGNIFICANCE: Heart valve tissue engineering has the potential to transform treatment for children born with defective pulmonary valves by providing living replacement tissue that can grow with the child. The design of tissue engineered heart valves is best informed by native valve properties, but native pediatric pulmonary valves have not been fully described to date. Here, we provide comprehensive characterization of the planar biaxial tensile behaviour, extracellular matrix composition and organization, and valvular interstitial cell phenotypes of pulmonary valves from piglets as a model for the native human pediatric valve. Together, these findings provide standards that inform engineered heart valve design towards generation of biomimetic pediatric pulmonary valves.

The aim is to assess for any lasting changes in corneal densitometry (CD) in patients who underwent small incision lenticule extraction (SMILE) and developed early transient postoperative corneal haze.

This retrospective chart review analyzed 98 eyes from 49 patients who underwent SMILE at the Hoopes Vision Clinic and had one-year postoperative Pentacam CD (Oculus Optikgeräte GmbH, Wetzlar, Germany). These were compared to 78 eyes from 42 unoperated myopic control patients with documented CD measurements. The preoperative CD, measured in grayscale units (GSU), was compared between SMILE patients who developed early transient haze ("transient haze group"), SMILE patients who did not build haze ("non-haze group"), and patients who did not undergo any refractive surgery ("controls"). The postoperative CD was compared between the transient haze and non-haze groups. Then, the postoperative CD was compared to the preoperative CD for the non-haze group and transient haze group, respectively.

The only significant difference in preoperative CD was in the central layer of the cornea at the 6-10 mm annulus between the non-haze group and controls (17.31 ±3.77 vs. 16.18 ±3.92 GSU; p=0.04). Postoperatively, there were no differences in CD between the non-haze group and the transient haze group (p<0.05). Comparing postoperative CD to preoperative CD, the non-haze group had increased CD in the 2-6 mm annulus of the anterior (1.54 ±0.45 GSU; p=0.001), posterior (0.65 ±2.28 GSU; p=0.032), and full thickness (0.72 ±0.29 GSU; p=0.006) layers of the cornea in addition to an increased CD in the 6-10 mm annulus of the posterior corneal layer (1.19 ±0.55 GSU; p=0.049). The transient haze group had an increased CD in the 2-6 mm annulus of the anterior (2.61 ±1.09 GSU; p=0.021) and full thickness (1.44 ±0.68 GSU; p=0.039) layers of the cornea.

There is no lasting difference in CD between patients who develop postoperative transient haze and those who do not after undergoing SMILE.

Kidney transplantation is the optimal treatment for end-stage kidney disease; however, premature allograft loss remains a serious issue. While many high-throughput omics studies have analyzed patient allograft biospecimens, integration of these datasets is challenging, which represents a considerable barrier to advancing our understanding of the mechanisms of allograft loss.

To facilitate integration, we have created a curated database containing all open-access high-throughput datasets from human kidney transplant studies, termed NephroDIP (Nephrology Data Integration Portal). PubMed was searched for high-throughput transcriptomic, proteomic, single nucleotide variant, metabolomic, and epigenomic studies in kidney transplantation, which yielded 9,964 studies.

From these, 134 studies with available data detailing 260 comparisons and 83,262 molecules were included in NephroDIP v1.0. To illustrate the capabilities of NephroDIP, we have used the database to identify common gene, protein, and microRNA networks that are disrupted in patients with chronic antibody-mediated rejection, the most important cause of late allograft loss. We have also explored the role of an immunomodulatory protein galectin-1 (LGALS1), along with its interactors and transcriptional regulators, in kidney allograft injury. We highlight the pathways enriched among LGALS1 interactors and transcriptional regulators in kidney fibrosis and during immunosuppression.

NephroDIP is an open access data portal that facilitates data visualization and will help provide new insights into existing kidney transplant data through integration of distinct studies and modules (https://ophid.utoronto.ca/NephroDIP).

Chronic graft-versus-host disease (cGvHD) is a multisystem disorder that occurs in recipients of allogeneic hematopoietic (alloHCT) stem cell transplants and is characterized by both inflammatory and fibrotic manifestations. It begins with the recognition of host tissues by the non-self (allogeneic) graft and progresses to tissue inflammation, organ dysfunction and fibrosis throughout the body. Oral cavity manifestations of cGVHD include mucosal features, salivary gland dysfunction and fibrosis. This review synthesizes current knowledge on the pathogenesis, diagnosis and management of oral cGVHD, with a focus on emerging trends and novel therapeutics. Data from various clinical studies and expert consensus are integrated to provide a comprehensive overview.

Acute lung injury (ALI) and its severe counterpart, acute respiratory distress syndrome (ARDS), are critical respiratory conditions with high mortality rates due primarily to acute and intense pulmonary inflammation. Despite significant research advances, effective pharmacological treatments for ALI and ARDS remain unavailable, highlighting an urgent need for therapeutic innovation. Notably, idiopathic pulmonary fibrosis (IPF) is a chronic, progressive disease characterized by the irreversible progression of fibrosis, which is initiated by repeated damage to the alveolar epithelium and leads to excessive extracellular matrix deposition. This condition is further complicated by dysregulated tissue repair and fibroblast dysfunction, exacerbating tissue remodeling processes and promoting progression to terminal pulmonary fibrosis. Similar to that noted for ALI and ARDS, treatment options for IPF are currently limited, with no specific drug therapy providing a cure. Histone deacetylase 3 (HDAC3), a notable member of the HDAC family with four splice variants (HD3α, -β, -γ, and -δ), plays multiple roles. HDAC3 regulates gene transcription through histone acetylation and adjusts nonhistone proteins posttranslationally, affecting certain mitochondrial and cytoplasmic proteins. Given its unique structure, HDAC3 impacts various physiological processes, such as inflammation, apoptosis, mitochondrial homeostasis, and macrophage polarization. This article explores the intricate role of HDAC3 in ALI/ARDS and IPF and evaluates its therapeutic potential the treatment of these severe pulmonary conditions.

C-X-C receptor 4(CXCR4) is widely considered to be a highly conserved G protein-coupled receptor, widely involved in the pathophysiological processes in the human body, including fibrosis. However, its role in regulating macrophage-related inflammation in the fibrotic process of prostatitis has not been confirmed. Here, we aim to describe the role of CXCR4 in modulating macrophage M1 polarization through glycolysis in the development of prostatitis fibrosis.

Use inducible experimental chronic prostatitis as a model of prostatic fibrosis. Reduce CXCR4 expression in immortalized bone marrow-derived macrophages using lentivirus. In the fibrotic mouse model, use adenovirus carrying CXCR4 agonists to detect the silencing of CXCR4 and assess the in vivo effects.

In this study, we demonstrated that reducing CXCR4 expression during LPS treatment of macrophages can alleviate M1 polarization. Silencing CXCR4 can inhibit glycolytic metabolism, enhance mitochondrial function, and promote macrophage transition from M1 to M2. Additionally, in vivo functional experiments using AAV carrying CXCR4 showed that blocking CXCR4 in experimental autoimmune prostatitis (EAP) can alleviate inflammation and experimental prostate fibrosis development. Mechanistically, CXCR4, a chemokine receptor, when silenced, weakens the PI3K/AKT/mTOR pathway as its downstream signal, reducing c-MYC expression. PFKFB3, a key enzyme involved in glucose metabolism, is a target gene of c-MYC, thus impacting macrophage polarization and glycolytic metabolism processes.

Macrophage-myofibroblast transformation (MMT) transforms macrophages into myofibroblasts in a specific inflammation or injury microenvironment. MMT is an essential biological process in fibrosis-related diseases involving the lung, heart, kidney, liver, skeletal muscle, and other organs and tissues. This process consists of interacting with various cells and molecules and activating different signal transduction pathways. This review deeply discussed the molecular mechanism of MMT, clarified crucial signal pathways, multiple cytokines, and growth factors, and formed a complex regulatory network. Significantly, the critical role of transforming growth factor-β (TGF-β) and its downstream signaling pathways in this process were clarified. Furthermore, we discussed the significance of MMT in physiological and pathological conditions, such as pulmonary fibrosis and cardiac fibrosis. This review provides a new perspective for understanding the interaction between macrophages and myofibroblasts and new strategies and targets for the prevention and treatment of MMT in fibrotic diseases.

When dysregulated, skin fibrosis can lead to a multitude of pathologies. We provide a framework for understanding the wide clinical spectrum, mechanisms, and management of cutaneous fibrosis encompassing a variety of matrix disorders, fibrohistiocytic neoplasms, injury-induced scarring, and autoimmune scleroses. Underlying such entities are common mechanistic pathways that leverage morphogenic signaling, immune activation, and mechanotransduction to modulate fibroblast function. In light of the limited array of available treatments for cutaneous fibrosis, scientific insights have opened new therapeutic and investigative avenues for conditions that still lack effective interventions.

Keloids are a common fibrotic disease of the skin, with the pathological hallmark of excessive extracellular matrix synthesis due to abnormal fibroblast activity. Since keloids clinically arise in areas of high mechanical tension, the mechanotransductory pathway may be attributed to its pathogenesis. We aimed to establish a preclinical platform to elucidate the underlying mechanism of keloid development and its clinical persistence.

We fabricated a mechanically stretchable polydimethylsiloxane cell culture platform; with its mimicry of the in vivo cyclic stretch of skeletal muscles, cells showed higher proliferation compared with conventional modalities.

In response to mechanical strain, TGF-β and type 1 collagen showed significant increases, suggesting possible TGF-β/Smad pathway activation via mechanical stimulation. Protein candidates selected by proteomic analysis were evaluated, indicating that key molecules involved in cell signaling and oxidative stress were significantly altered. Additionally, the cytoskeletal network of keloid fibroblasts showed increased expression of its components after periodic mechanical stimulation.

Herein, we demonstrated and validated the existing body of knowledge regarding profibrotic mechanotransduction signaling pathways in keloid fibroblasts. Cyclic stretch, as a driving force, could help to decipher the tension-mediated biomechanical processes, leading to the development of optimized therapeutic targets.

Idiopathic pulmonary fibrosis (IPF) is an age-related disease featured with abnormal fibrotic response and compromised lung function. Cellular senescence is now considered as an essential driving mechanism for IPF. Given the poor knowledge of the mechanisms underpinning IPF progression, understanding the cellular processes and molecular pathways is critical for developing effective therapies of IPF.

Lung fibrosis was induced using bleomycin in C57BL/6 mice. Cellular senescence was measured by immunofluorescence. The effects of FGF-4 on fibroblast activation markers and signaling molecules were assessed with western blot and qPCR.

We demonstrated elevated abundance of senescent mesenchymal stem cells (MSCs) in IPF lung tissues, which was tightly correlated with the severity of pulmonary fibrosis in vivo. In addition, senescent MSCs could effectively induce the phenotype of pulmonary fibrosis both in vitro and in vivo. To further confirm how senescent MSCs regulate IPF progression, we demonstrate that FGF-4 is significantly elevated in senescent MSCs, which can induce the activation of pulmonary fibroblasts. In vitro, FGF-4 can activate Wnt signaling in a FOXM1-dependent manner. Inhibition of FOXM1 via thiostrepton effectively impairs FGF-4-induced activation of pulmonary fibroblast and dramatically suppresses the development of pulmonary fibrosis.

These findings reveal that FGF-4 plays a crucial role in senescent MSCs-mediated pulmonary fibrogenesis, and suggests that strategies aimed at deletion of senescent MSCs or blocking the FGF-4/FOXM1 axis could be effective in the therapy of IPF.

Chronic nonhealing skin wounds, characterized by reduced tissue contractility and inhibited wound cell survival under hyperglycemia and hypoxia, present a significant challenge in diabetic care. Here, an advanced self-contraction bioactive core-shell microgel assembly with robust tissue-adhesion (SMART-EXO) is introduced to expedite diabetic wound healing. The SMART-EXO dressing exhibits strong, reversible adhesion to damaged tissue due to abundant hydrogen and dynamic coordination bonds. Additionally, the core-shell microgel components and dynamic coordination bonds provide moderate rigidity, customizable self-contraction, and an interlinked porous architecture. The triggered in situ self-contraction of the SMART-EXO dressing enables active, tunable wound contraction, activating mechanotransduction in the skin and promoting the optimal fibroblast-to-myofibroblast conversion, collagen synthesis, and angiogenesis. Concurrently, the triggered contraction of SMART-EXO facilitates efficient loading and on-demand release of bioactive exosomes, contributing to re-epithelialization and wound microenvironment regulation in diabetic mice. RNA-seq results reveal the activation of critical signaling pathways associated with mechanosensing and exosome regulation, highlighting the combined biomechanical and biochemical mechanisms. These findings underscore SMART-EXO as a versatile, adaptable solution to the complex challenges of diabetic wound care.

Mesenchymal stromal cells are suggested to play a critical role in Crohn's disease [CD]-associated fibrosis. MAPKAPK2 [MK2] has emerged as a potential therapeutic target to reduce inflammation in CD. However, the cell-specific pattern of phospho-MK2 activation and its role in CD-associated fibrosis are unknown. The objectives of this study were to evaluate cell-specific changes in MK2 activity between predominantly inflammatory CD vs CD with fibrotic complications and define the role of stromal cell-specific MK2 activation in CD-associated fibrosis.

CD tissue, CD tissue-derived mesenchymal stromal cells known as myo-/fibroblasts [CD-MFs], and fibroblast-specific MK2 conditional knockout [KO] mice were used.

In the inflamed area of predominantly inflammatory CD, high MK2 activity was equally distributed between mesenchymal and haematopoietic cells. By contrast, in CD with fibrotic complications, high MK2 activity was mostly associated with mesenchymal stromal cells. Using ex vivo CD tissue explants and an IL-10KO murine colitis model, we demonstrated that pro-fibrotic responses are significantly reduced by treatment with the MK2 inhibitor PF-3644022. Inhibition of MK2 activity in primary cultures of CD-MFs significantly reduced basal and TGF-β1-induced profibrotic responses. Using fibroblast-specific MK2 knockout mice in chronic dextran saline sulphate colitis, we demonstrated that fibroblast intrinsic MK2 signalling is among the key processes involved in the chronic inflammation-induced profibrotic responses.

Our data suggest that activation of MK2 within fibroblasts contributes to the chronic inflammation-induced fibrosis in CD and that targeting MK2 has potential for the development of novel therapeutic approaches for fibrosis in CD.