Wound Healing Research Articles

Chronic rhinosinusitis (CRS) may require endoscopic sinus surgery (ESS) as a complement to medical therapies. Type 2 dominant inflammation underlies nasal polyposis (CRSwNP), and is characterized by eosinophilic inflammation, poor therapeutic response, and high recurrence risk. Type 2 inflammation was defined as eosinophilic CRS (ECRS) based on clinical presentation and laboratory findings. Unfavorable wound healing, associated with elevated levels of matrix metalloproteinase 9 (MMP-9), can lead to failure of ESS. Doxycycline with its antibiotic, anti-inflammatory, and anti-protease (including MMP-9) properties may improve postoperative healing. Thirty-three adult CRS patients scheduled for ESS were randomly assigned to receive either doxycycline or placebo for 56 days postoperative and were followed up until 48 weeks post-ESS. Postoperative wound healing was assessed endoscopically. Nasal secretions, serum, and patient-reported outcome measures were collected throughout the study. Nasal secretions were analyzed to monitor local myeloperoxidase (MPO), MMP-9, eosinophilic cationic protein (ECP), and IgE levels from baseline until 48 weeks post-ESS. Proteomics analysis, using LC-MS/MS, of nasal secretions was performed at baseline, 2- and 8-weeks post-ESS to investigate wound healing mechanisms. Postoperative doxycycline significantly improved wound healing quality in patients with CRSwNP or ECRS. Increased local MMP-9, neutrophilic (MPO), and eosinophilic (ECP) inflammation post-ESS was dampened by doxycycline. Wound healing and extracellular matrix remodeling processes were upregulated by doxycycline treatment. In contrast, the placebo group showed increased neutrophilic inflammation and delayed healing. Postoperative doxycycline therapy facilitated wound healing in CRSwNP and ECRS patients and suppressed local mucosal inflammation.

Background: While macrophage to myofibroblast transition (MMT) has been reported in various tissues and diseases, it has not been studied in wound healing. We sought to identify the epigenetic mechanisms that control MMT during wound repair and if MMT is epigenetically altered in diabetic wound healing. Methods: We used a combination of transgenic murine models, loss of function approaches in vitro and in vivo , pharmacologic inhibition in vivo , flow cytometry, spatial sequencing, and single cell RNA sequencing (scRNA-seq) in human and murine wounds. Results: Flow cytometry of whole wounds from Col1a1-GFP reporter mice identified a CD3 - CD19 - Ly6G - CD11b + F4/80 + resident macrophage population undergoing MMT from day 5 to 7 post-wounding (p<0.05). We identified the H3K36 methyltransferase Whsc1 was upregulated in wound macrophages in response to TGFβ, and siRNA knockdown of Whsc1 in bone marrow derived macrophages (BMDMs) decreased expression of Acta2, Col1a1, Col3a1 and H3K36me2 at fibrotic promoters (p<0.05). Myeloid-specific Whsc1 loss in Whsc1f lox/flox ;Lyz2 Cre+ mice impaired wound healing and decreased Acta2 , Col1a1 , and Col3a1 expression in wound macrophages. Local pharmacologic inhibition of Whsc1 in vivo disrupted wound healing (p<0.05). Flow cytometry of wounds isolated from Col1a1-GFP mice revealed fewer resident macrophages from mice on a diabetic diet (DIO) (2%) versus normal diet (15%) (p<0.05). Spatial sequencing of human wounds identified resident macrophages (F CGR1A, ITGAM, MERTK, CCR2, SIGLEC1, CX3CR1, CD163, LYVE1, MRC1, TIMD4, and CD9 positive) represented 4.4% of total macrophages ( CD14, CD16 , and CD68 positive ), exhibited increased TGFB1 expression compared to non-resident macrophages, and were in closer proximity to fibroblast neighbors. scRNA-seq of human wounds revealed that Whsc1 expression was decreased in macrophages from diabetic wounds (p<0.05). In DIO BMDMs, Whsc1 was absent at fibrotic promoters after TGFβ treatment and remained at NFkB-regulated inflammatory gene promoters ( Il1b, Il6, Tnf ) bound to RelA. RelA knockdown in DIO BMDMs increased Whsc1 at fibrotic promoters and lead to increased fibrotic gene expression (p<0.05). Conclusion: We show that MMT occurs in the resident macrophage subpopulation during wound healing and is regulated by TGFβ-Whsc1, which is disrupted in diabetic wound healing. These data identify the RelA-Whsc1 interaction as a novel target in diabetic wound treatment.

Background: The treatment goals for chronic limb-threatening ischemia (CLTI) include limb salvage, pain control, preservation of limb function, and wound healing. Patients with CLTI are typically elderly and suffer from multiple comorbidities, leading to a poor overall prognosis. Therefore, comprehensive multidisciplinary treatment approaches are often required in addition to limb revascularization. In this study, we investigated prognostic factors in CLTI patients who underwent endovascular therapy (EVT). Methods and Results We analyzed 141 patients who underwent EVT below the popliteal artery between April 2014 and December 2018. The 1-year survival rate was 83.6%. When comparing the survival and non-survival groups at 1 year, the survival group was significantly younger (70.8 ± 11.2 vs. 76.2 ± 9.7 years, p = 0.04), had lower LDL-C levels (85.8 ± 35.2 vs. 110.3 ± 38.7 mg/dL, p = 0.02), and a higher proportion of patients were ambulatory at discharge (67.9% vs. 19.0%, p < 0.01). No significant differences were found in the presence of chronic kidney disease, ischemic heart disease, lower limb amputation, or nutritional status. Multivariate analysis identified ambulation at discharge as an independent predictor of 1-year survival. The 5-year follow-up rate was 66%, and the 5-year survival rate among followed patients was 33.3%. In the survival group, patients were younger (65.9 ± 10.5 vs. 74.1 ± 10.5 years, p < 0.01), had higher eGFR (32.4 ± 32.2 vs. 20.6 ± 20.9 mL/min/1.73m 2 , p = 0.04), higher hemoglobin levels (11.8 ± 1.7 vs. 10.7 ± 2.1 g/dL, p < 0.01), a greater proportion had good nutritional status (74.2% vs. 35.5%, p < 0.01), and a higher rate of ambulation at discharge (87.1% vs. 44.3%, p < 0.01). Multivariate analysis identified younger age, higher eGFR, better nutritional status, and ambulation at discharge as independent predictors of 5-year survival. Conclusion: The presence or absence of lower limb amputation, whether minor or major, and the length of hospital stay did not significantly affect prognosis. While advances in revascularization techniques have improved limb salvage and wound healing, our findings indicate that achieving ambulation is an even more critical determinant of long-term outcomes.

Background: Aspirin therapy is well-established for secondary prevention of cardiovascular events; however, its role in modifying amputation outcomes in patients with peripheral artery disease (PAD) remains unclear. Research Question: Does aspirin therapy influence the likelihood of major versus minor amputations in PAD? Aims: To evaluate the association between aspirin use and the level of lower extremity amputation (major vs. minor) in patients with PAD. Methods: We conducted a retrospective review of 387 PAD patients undergoing lower extremity amputation, classified as major (n=122) or minor (n=262) procedures. The cohort had a mean age of 64.1 ± 12.8 years and was predominantly male (72.1%). Cardiometabolic comorbidities were highly prevalent, with diabetes in 95.1%, hypertension in 88.4%, and hyperlipidemia in 81.1%. Among these patients, 239 (61.8%) were receiving aspirin therapy. We assessed the prevalence of cardiovascular risk factors, amputation level, reintervention needs, wound healing, and post-operative outcomes. Results: Aspirin users exhibited a substantial burden of comorbid conditions, with diabetes present in 96.2%, hypertension in 92.9%, and hyperlipidemia in 88.3%. Major amputations occurred in 16.3% of aspirin users, while 15.5% underwent minor amputations. Logistic regression demonstrated no significant association between aspirin use and lower odds of major amputation compared to minor amputation (OR 1.07; 95% CI: 0.62–1.85; p=0.806). Secondary amputations occurred in 32.6% of the total cohort, with 30.7% requiring reinterventions. Cardiovascular events post-amputation were notable, with 19.1% experiencing myocardial infarction and 1.0% suffering a stroke. Wound healing was achieved in 78.8%, though recurrent ulceration occurred in 19.4%. Mortality during follow-up was 15.2%. Among aspirin users with available data, disease control was suboptimal: only 56.5% had well-controlled diabetes (HbA1c ≤ 7.5%), 38.1% had LDL cholesterol <2.0 mmol/L, and 59.8% had blood pressure <140/90 mmHg. Notably, none met the prealbumin threshold for adequate nutritional status. Conclusion: In this high-risk PAD population, aspirin use did not confer a statistically significant reduction in the odds of major versus minor amputation. The high prevalence of cardiometabolic risk factors, suboptimal risk factor control, and significant rates of secondary procedures highlights the need for enhanced vascular care.

Melanin, a biopolymer synthesized from tyrosine, plays diverse and essential roles in insect physiology, encompassing immune defense, thermoregulation, and environmental adaptation. This review synthesizes three decades of research (1990–2024) to elucidate the enzymatic pathways, regulatory mechanisms, and adaptive functions of melanin across insect taxa. Key enzymes such as phenoloxidase and tyrosinase mediate melanin biosynthesis and are central to pathogen encapsulation and wound healing, while also contributing to thermal regulation and Ultraviolet Radiation (UV) protection in extreme environments. The review integrates recent advances on hormonal and genetic regulation, emphasizing the roles of juvenile hormones, ecdysteroids, and transcription factors in modulating melanogenesis. It also identifies critical gaps in understanding transcriptional, epigenetic, and environmental regulation of melanin synthesis. By highlighting melanin’s multifunctionality and evolutionary significance, this review provides a framework for future studies linking molecular mechanisms with ecological adaptation and offers potential applications in pest management and insect resilience under climate change.

Introduction: Sternal wound infections (SWIs) are serious complications following median sternotomy in cardiac surgeries such as coronary artery bypass grafting (CABG), valve replacements, and atrial septal defect (ASD) repairs. Topical vancomycin powder (VP) has been proposed as a preventive measure, but its efficacy remains uncertain. Research Question: Does intraoperative vancomycin powder reduce SWIs and improve early postoperative outcomes in cardiac surgery via median sternotomy? Methods: In this single-blinded, single-center randomized controlled trial in Karachi, Pakistan (ClinicalTrials.gov ID: NCT06329016), 24 adults undergoing CABG, valve replacement, or ASD repair via median sternotomy were randomized to receive either 1g of vancomycin powder (n=12) or no powder (control, n=12) prior to sternal closure. SWIs were assessed clinically at 48 hours, day 7, and 1 month based on redness, tenderness, swelling, and discharge. Additional outcomes included ICU/ward stay and wound healing. Results: Of 24 randomized patients (12 control, 12 VP), the control group had 6 females; VP group had 4. Surgical types and operative durations were comparable; 10 VP patients had procedures <180 minutes. No open-chest cases occurred. SWIs were seen in 33.3% (4/12) of control vs 8.3% (1/12) of VP group (p=0.140). One control patient required re-exploration; none in VP group did. ICU stay <3 days occurred in 58.3% (control) vs 83.3% (VP); ICU stay >3 days in 41.7% vs 16.7%, respectively. Ward stay >10 days was significantly higher in the control group (75.0%) vs VP (8.3%) (p=0.001). Conversely, 25.0% of control and 91.7% of VP patients had ward stays <10 days. Re-admissions occurred in 3/7 infected control patients (42.9%) and 1/12 VP patients (8.3%). Wound discharge occurred in 3/4 control and 1/1 VP patient. Serous discharge occurred in 1 control patient; purulent in 2 control and 1 VP patient. No vancomycin-related adverse events were observed. Conclusion: Topical vancomycin powder may enhance wound healing and reduce hospital stay in cardiac surgery patients via median sternotomy. Though the reduction in SWI was not statistically significant, results support a favorable safety and efficacy profile, warranting further study in larger trials.

Wound infection complicated by excessive inflammation remains a persistent challenge in clinical healthcare. Curcumin (Cur), a natural diketone compound, holds therapeutic potential in treating infected wounds. However, its application is limited by poor aqueous dispersibility and low stability. To overcome this dilemma, a versatile capsule as an effective Cur carrier is developed by encapsulating Cur in succinic acid-modified cyclodextrin via hydrophobic interactions, and then loading it into a Zn2+-mediated crosslinked injectable hydrogel for infected wound healing. The composite hydrogel exhibits adjustable rheological properties, modulus, swelling ratios, and degradation rate by control over Zn2+ concentration. This unique tactic enables the sustained Cur release, ensuring long-term antioxidant activity and reactive oxygen species (ROS) scavenging. An in vivo experiment in a rat S. aureus-infected wound model demonstrates that the composite hydrogel significantly accelerates wound healing by massacring bacteria, inhibiting inflammation, as well as promoting collagen deposition and angiogenesis. Overall, this effort paves the way for arming Cur, offering a potent antibiotic-free candidate for bacteria-invaded wound management.

Fluoxastrobin (FLUO) is a fungicide from strobilurin family used widely worldwide. The use of FLUO pesticide is on the rise and this phenomenon is accompanied by a series of concerns such as endocrine disruption. In order to determine the potential toxic effects of FLUO, cell culture, gene expression and molecular docking assays were conducted as it is crucial to determine the interaction between chemicals and nuclear receptors in order to estimate and understand the impact of the chemical. This study analyzed the quantum properties of FLUO at the molecular quantum mechanical level using Density Functional Theory (DFT) with the B3LYP/6-311 + + G(d, p) and cc-pVDZ basis sets including the HOMO-LUMO energy gap, chemical reactivity descriptors, molecular electrostatic potential (MEP) surface calculation. In order to investigate molecular characteristics, topological (AIM, RDG) and Natural Bonding Orbitals (NBO) investigations were conducted. Molecular docking studies were performed with the title compound in the active sites of the proteins selected because of their role in xenobiotic metabolism. The docking result was determined to be a significant factor in bioactivity, a finding that is corroborated by the cytotoxic analysis of the FLUO compound. Density Functional Theory (DFT) computations are used to support molecular docking analysis. Toxicity of FLUO was tested on MDA-MB-231 cells using XTT and wound healing assays. IC50 value of FLUO was determined as 6,9µg/ml. The impact of FLUO exposure at molecular level was assessed using qRT-PCR by determining the expression levels of PPARy, AhR and PXR genes where no statistically significant change was found.

Background: The goal of tissue regeneration is to restore structure and function. In adult regenerative wound healing, dermal fibroblasts exhibit multipotency and can be reprogrammed into lineages such as hair follicle cells and adipocytes, etc. Neural cell adhesion molecule 1 (NCAM1), a membrane-bound adhesion protein expressed in dermal fibroblasts, plays a key role in cell-cell and cell-matrix interactions and has been implicated in fate transitions during tissue remodeling. NCAM1 is absent in normal endothelium but is aberrantly expressed in tumor-derived endothelial cells, where it promotes capillary morphogenesis. These observations suggest that NCAM1+ fibroblasts may represent a progenitor-like state more capable of endothelial conversion than NCAM1- cells. While angiogenesis is the main vascularization process in adult wounds, vasculogenesis from progenitors like fibroblasts may also contribute. Fibroblast-to-endothelial reprogramming has been demonstrated in vitro using defined reprogramming factors, but its in vivo evidence remains to be investigated. We hypothesized that NCAM1+ dermal fibroblasts give rise to a subset of regenerated endothelial cells. Aims: (1) Characterize vasculature formation during regenerative wound healing (2) Identify progenitor populations and reprogramming cues, including transcription factors and adhesion molecules Method: Using a wound-induced hair neogenesis (WIHN) mouse model, we performed scRNA sequencing and RNA velocity analyses on post-wounding day 14. Wholemount immunostaining assessed vascular morphology and cell identity. NCAM1-CreERT2×ROSA26 reporter mice for lineage tracing. Results: The regenerated wound bed showed two contrasting vasculature patterns: disrupted, discontinuous vessels in the regenerating wound center and organized vasculature in the wound margin. scRNA-seq and velocity analyses indicated PECAM1+ cells may originate from NCAM1+ fibroblast-like cells that also expressed fibroblast-to-endothelial cells reprogramming factors such as FOXO1, TAL1 and SOX17. Wholemount staining revealed individual cells and a fraction of endothelial cells co-expressing PECAM1, PDGFRα, and NCAM1 in the capillary-like vasculature in wound dermis. Conclusion: Our findings support vasculogenesis during regenerative wound healing, with NCAM1+ fibroblasts contributing to endothelial cell populations. These results provide new insights into fibroblast-endothelial plasticity and vascular regeneration in adult tissue regeneration.

Background: Brain microvascular endothelial cells (BMECs) are essential for maintaining blood-brain barrier (BBB) integrity and cerebrovascular homeostasis. Mitochondrial dysfunction is increasingly recognized as a contributor to vascular pathology in neurodegenerative diseases. While rotenone, a mitochondrial complex I inhibitor, is known to induce oxidative stress in neurons, its effects on BMEC function remain poorly defined. Objective: To investigate how mitochondrial oxidative stress affects BMEC migration and angiogenic capacity, and whether targeting mitochondrial ROS with mitoTEMPO can reverse these effects. Methods: Human brain endothelial cells (HBECs; passage 8) were treated with 0.5 µM rotenone in the presence or absence of 10 µM mitoTEMPO for twelve hours. Cell migration was assessed using a wound healing assay, and angiogenic function was evaluated via Matrigel tube formation. Mitochondrial membrane potential (ΔΨm) was measured using TMRE uptake. Wound closure and tube length were quantified using ImageJ. Statistical analysis was performed using one-way ANOVA with Tukey’s post-hoc test. Results: Rotenone significantly impaired HBEC migration, reducing wound closure by 4.39-fold compared to control (Rotenone: 20.9 ± 4.4%; Control: 4.75 ± 2.45%; p = 0.023, n = 3–4 wells). MitoTEMPO co-treatment significantly improved migration ( p < 0.05 vs. rotenone). In the tube formation assay, rotenone reduced total tube length by 45% ( p = 0.000). Co-treatment with mitoTEMPO partially rescued tube formation, showing a 31% improvement (trend-level, p = 0.058). Notably, mitoTEMPO did not restore the rotenone-induced loss of mitochondrial membrane potential, suggesting that its protective effects are independent of ΔΨm. Conclusions: Mitochondrial ROS impairs endothelial migration and angiogenesis in brain endothelial cells. MitoTEMPO partially rescues these functions, despite persistent mitochondrial membrane depolarization. These findings suggest that mitochondrial oxidative stress, rather than loss of ΔΨm, plays a primary role in BMEC dysfunction and may represent a therapeutic target in cerebrovascular disease.

Introduction: Endothelial cell dysfunction causes recruitment of inflammatory cells to the intima, initiating atheromatous plaque build-up. Atherosclerosis underlies myocardial infarction and stroke which remain leading causes of death in the US. Identifying key regulators that limit endothelial dysfunction is critical. We uncovered a previously unrecognized role of an endocytic adaptor protein, Disabled homolog 2 (Dab2), which regulates endocytosis and lysosomal degradation of receptor tyrosine kinases such as VEGFR2. We found that endothelial Dab2 promoted VEGF signaling during angiogenesis in diabetic wound healing. However, the mechanism how Dab2 in the endothelial cells protected endothelium function in atherosclerosis is unknown. Hypothesis: Endothelial Dab2 protects endothelial function under atherogenic conditions by promoting pulsatile shear (PS)-induced PI3K-Akt-eNOS signaling via endosomal trafficking. PS increases transcription factor KLF4 expression which activates Dab2 expression. Restoring Dab2 in the endothelium offers a therapeutic strategy to limit plaque progression. Methods and Results: We found reduced endothelial Dab2 expression in human atherosclerosis and ApoE-/- mice. We generated endothelial-specific inducible Dab2 knockout mice (EC-Dab2iKO) and crossed to ApoE-null background (EC-Dab2iKO/ApoE -/- ). Western diet-fed EC-Dab2iKO/ApoE -/- mice exhibited heightened arterial inflammation, more severe plaque formation, increased macrophage infiltration and reduced plaque stability. Single-cell RNA-seq, qPCR and western blot revealed that endothelial Dab2 depletion significantly upregulated pro-inflammatory markers and shear stress-related atherosclerotic pathways, indicating Dab2 protect against endothelial dysfunction by increasing PS-dependent eNOS activation via endosomal PI3K-Akt activation. ATAC-seq and ChIP-qPCR showed that KLF4 binds to Dab2 promoter. Using an in vitro PS flow channel to mimic atheroprotective flow, we found both Dab2 and KLF4 were increased. Using an endothelial-targeted engineered nanoparticle, we delivered Dab2 mRNA to the atherogenic endothelium to restore Dab2 function. It increased Dab2 level in the atheroma which restrains plaque progression in ApoE-/- mice. Conclusions: Our study reveals Dab2 as a key protector of atherogenic endothelium, linking PS and endothelial homeostasis via KLF4 and PI3K-Akt-eNOS signaling. Targeted restoration of Dab2 may represent a promising therapeutic approach for atherosclerosis.

Background: Vascular smooth muscle cells (SMCs) contribute significantly to heritable coronary artery disease (CAD) risk and undergo phenotypic transitions in the intimal plaque during atherosclerosis. ZEB1 is a master regulator of epithelial-to-mesenchymal transition, that has been associated with CAD through human genetic studies. ZEB1 orchestrates cell state changes through modulation of TGFβ signaling and numerous epigenetic regulators. However, the mechanisms underlying the genetic association between ZEB1 and CAD remain unexplored. Methods: Single-cell RNA and ATAC sequencing on lineage-traced SMCs from the atherosclerotic aortic roots of SMC-specific Zeb1 knockout mice ( Zeb1 -KO; Myh11Cre ERT2 , ROSA tdT/+ , ApoE -/- ) were collected after 16 weeks on high-fat diet to characterize the changes in transcriptomic and epigenetic landscape. siRNA knockdown of ZEB1 in combination with TGFβ and IFNγ stimulations were performed in vitro on human coronary artery SMCs (HCASMCs) to validate in vivo findings. Results: Zeb1 -KO single cell RNA and ATAC sequencing showed the emergence of a novel epithelial-like SMC state characterized by robust ectopic activation of tricellular tight junction and cell polarity genes. Despite this increase in epithelial features, Zeb1 -KO also led to an increase in phenotypically transitioning SMCs contributing to the intimal plaque, accompanied by multi-fold enrichment in interferon-gamma (IFNγ) signaling targets. Motif analysis revealed near complete opening of chromatin accessibility at previously closed ZEB1 binding motifs, implicating ZEB1 mediated epigenetic repression. In vitro co-stimulation with TGFβ and IFNγ showed that si ZEB1 abolished the inhibitory effect of TGFβ on IFNγ signaling and demonstrated enriched for migratory and growth factor response functions by bulk RNAseq. Cell-cell signaling analysis by MultiNicheNet identified ectopic expression of migratory marker Lamc2 and concurrent increases in its interacting integrin partners in Zeb1 -KO SMCs. Furthermore, si ZEB1 HCASMCs also showed elevated expression of LAMC2 , its integrin interacting partners, as well as increased wound healing capacity by scratch assay. Conclusion: We identify ZEB1 as a critical epigenetic repressor required for the maintenance of the SMC cell state, suppressing epithelial marker expression and modifying cellular response to interferon signaling to ultimately augment SMC phenotypic transitions, linking genetic association between ZEB1 and CAD risk.

People with chronic limb-threatening ischemia lack Food and Drug Administration-approved therapies for wound healing, creating an unmet need for novel approaches. Prior studies of biologics in chronic limb-threatening ischemia have largely targeted end-stage patients with amputation-free survival as the primary outcome. This trial evaluated the efficacy of intramuscular administration of AMG0001, a plasmid encoding human HGF (hepatocyte growth factor), to promote ulcer healing in patients with chronic limb-threatening ischemia and neuroischemic ulcers. LEGenD-1 was a double-blind, randomized, placebo-controlled phase II trial conducted at 22 US sites. Seventy-five participants with neuroischemic ulcers and toe pressure or transcutaneous oxygen pressure between 30 and 59 mm Hg were randomized to receive AMG0001 at 4 mg, 8 mg, or placebo. Injections were administered intramuscularly along an angiographically guided target artery path on days 0, 28, 56, and 84. The 2 coprimary end points were time to complete healing and the proportion of subjects with ulcers healed by 6 months in a pooled AMG0001 analysis. Secondary end points included healing at 12 months, ulcer recurrence, and hemodynamic changes. Baseline characteristics were comparable across groups (mean age 62.6 years; 80.0% male; 70.7% with diabetes). Mean toe pressure was 46.1 mm Hg, and transcutaneous oxygen pressure was 49.8 mm Hg. Median time to healing was significantly shorter with AMG0001 versus placebo (84 versus 280 days; P=0.007); 4 mg: 98 days (P=0.017); 8 mg: 84 days (P=0.022). At 6 months, 63.3% of AMG0001-treated participants healed versus 38.5% of placebo (P=0.053). At 12 months, healing rates were 77.6% versus 46.2% (P=0.010). Adverse events were similar across groups. Anatomically targeted intramuscular delivery of AMG0001 significantly accelerated healing in patients with moderate chronic limb-threatening ischemia and neuroischemic ulcers and may represent a promising nonsurgical therapeutic strategy. URL: https://www.clinicaltrials.gov; Unique identifier: NCT04267640.

Background: We have previously reported that Sorbs2 (sorbin and SH3 domain 2) knockout mice have significant cardiac structural and electrical remodeling, including atrial enlargement and fibrosis. The mechanisms of such changes were unknown. Hypothesis: We hypothesized that loss of Sorbs2 in cardiac fibroblasts promotes profibrotic signaling pathways and alters the balance between matrix metalloproteinases (MMPs), and their inhibitors (TIMPs) resulting in excessive collagen deposition in the atria. Methods: We used Sorbs2 global knockout ( Sorbs2 KO) mice and age-matched wild-type (WT) controls at 4 to 5 months of age. Left atrial fibrosis was quantitated by Masson's trichrome staining in serial sections. Scratch wound healing assays and transwell migration assays were performed in isolated Sorbs2 KO and WT atrial fibroblasts. Protein expression was determined by Western blots. Interleukin-6 (IL-6) production in cultured fibroblast supernatants was measured by ELISA. Results: Sorbs2 KO mice showed significant increase in atrial diameter (16.6 ± 1.5 mm vs 12.0 ± 1.1 mm in WT; n=3, p < 0.05) and atrial fibrosis (fraction of fibrotic areas: 18.6± 2.9 % vs. 7.6 ± 0.9 % in WT; p < 0.01). Collagen 1 and collagen 3 protein levels in Sorbs2 KO mouse atria were 1.8-fold and 1.7-fold higher than those of WT respectively. Sorbs2 KO atrial fibroblasts showed impaired function with significantly reduced migration and slower scratch-wound closure (migration area after 24h: 18.5 ± 3.8 % vs 70.1 ± 6.7 % in WT; n=6, p < 0.01).Moreover, transforming growth factor β1 (TGF-β1), α-smooth muscle actin, and periostin expression levels were significantly reduced in isolated fibroblasts and atrial myocardia from Sorbs2 KO mice, suggesting that fibrosis is not caused by TGF-b1-dependent mechanisms or from myofibroblast transformation. Analysis of ECM proteins showed significant downregulation of MMP1 and MMP3 but upregulation of TIMP1, while TIMP3 was unchanged. Consistent with a pro-inflammatory phenotype, Sorbs2 KO atrial fibroblasts secreted higher IL-6 levels at baseline (3303± 463 pg/mL vs. 2075 ± 731 pg/mL in WT; n=6, p < 0.01) and with LPS stimulation (7791 ± 604 pg/mL vs. 5588 ± 763 pg/mL in WT; n=6, p < 0.01). Conclusion: Sorbs2 deficiency is associated with abnormal atrial fibroblast function showing impaired migration and scratch wound healing, as well as increased IL-6 production and imbalanced MMP/TIMP. These changes result in collagen accumulation and enhanced fibrosis.

When a percutaneous metallic implant breaches the skin barrier, the lack of peri-implant soft tissue sealing arising from a foreign body reaction and epithelial downgrowth results in delayed wound healing and closure. This facilitates microbial pathogen entry, leading to infection, inflammation, and ultimately, peri-implantitis. Toward this end, bioglue formulations of -human hair keratin (HHK) and chicken feather keratin coupled with polyphenols, dopamine (DOPA), quercetin (Q), and tannic acid (TA) were developed for peri-implant soft tissue sealing. A freeze-thaw gelation mediated by thiol recombination of reduced keratins was employed for attachment of soft tissue (porcine intestine) to titanium. Lap shear tests revealed that the adhesion strength of reduced keratins improved with polyphenol addition, with a maximal glue strength exhibited by HHK + TA (10:1 w/w) when applied between the porcine intestine and titanium. Rheological characterization ascertained shear-thinning behavior and injectability of the glues into wet aqueous media and dry surfaces. Despite inferior glue strength to commercial ethyl 2-cyanoacrylate bioglue, the keratin ± polyphenol glues were more skin compatible, evidenced by greater viability and proliferation of immortalized human skin epidermal keratinocytes (HaCaT) and equine dermal fibroblasts (E. Derm NBL6). Furthermore, the antioxidant activity of keratin ± polyphenol glue formulations conferred greater anti-inflammatory activity in bacterial lipopolysaccharide stimulated RAW 264.7 murine macrophages. Taken together, the application of keratin ± polyphenol glues for soft tissue sealing may be a promising approach to mitigate peri-implantitis around transcutaneous metallic prostheses.

Electrical stimulation (ES) via rigid electrodes near the wound is a promising approach for treating chronic wounds, but it cannot stimulate the entire wound area or address infected wounds. Conductive hydrogels enable both endogenous and exogenous current conduction, promote intercellular signaling, and conduct current from external ES to the wound site, thereby enhancing cell migration and angiogenesis. The combined hydrogel dressing/ES treatment strategy can promote wound healing throughout the entire healing process. Despite significant achievements in accelerating wound healing as electroactive dressings, conductive hydrogels face multiple challenges: an imbalance between high conductivity and mechanical properties, lack of antimicrobial activity, and poor adhesion. This study designed and assembled a CuNP-functionalized bacterial cellulose hydrogel exhibiting outstanding antimicrobial properties and favorable mechanical performance. This hydrogel exhibits conductivity comparable to human skin (41.25 ms/m) and mechanical strength (1120% tensile strain), while maintaining good tissue adhesion (up to 27.34 kPa on pig skin) and antibacterial efficacy (>99%). When combined with exogenous ES on diabetic wounds, the hydrogel promotes collagen deposition and angiogenesis, accelerating skin tissue remodeling (reducing wound area to 24.3% within 7 days). Additionally, it functions as a sensor for monitoring human motion and microexpressions. This conductive hydrogel demonstrates significant potential in chronic wound healing and bioelectronics.

Introduction Wound healing and skin regeneration have become global health challenges, causing substantial harm to the physical and mental health. Many studies have shown that human umbilical cord mesenchymal stem cell-derived exosomes (hUCMSC-Exos) can promote tissue repair and regeneration. However, the efficacy and underlying mechanisms of hUCMSC-Exos in treatment remain to be elucidated. Methods hUCMSC-Exos were isolated by ultracentrifugation and characterized by analyses of nanoparticle tracking analysis (NTA), western blotting (WB), and transmission electron microscopy (TEM). The efficacy of hUCMSC-Exos on the proliferation, migration, and angiogenesis potential of fibroblasts and endothelial cells were examined in vitro . The effects of the hUCMSC-Exos on wound healing were assessed by wound closure rate, histological and immunohistochemical analyses. miRNAs and their target genes that may play a role in skin repair and regeneration were identified and predicted through bioinformatics analysis. Results In vitro analysis indicated that hUCMSC-Exos are easily internalized by human umbilical vein endothelial cells (HUVECs) and human skin fibroblasts (HSFs), significantly promoting the proliferation and migration of HSFs, as well as the proliferation and tube formation of HUVECs. Analysis of skin wound models indicated that hUCMSC-Exos significantly accelerate wound healing by reducing inflammation, stimulating angiogenesis, and promoting the formation of extracellular matrix. Mechanistically, bioinformatics analysis suggests that Unc-51-like autophagy activating kinase 2 (ULK2), Collagen Type XIX Alpha 1 Chain (COL19A1), and Interleukin-6 Signal Transducer (IL6ST) are potential key molecules involved in the regulation of wound repair by hUCMSC-Exos. Discussion In summary, hUCMSC-Exos regulate the functions of HUVEC and HSFs through miRNA, significantly promoting wound healing and tissue repair, suggesting that hUCMSC Exos therapy is a promising therapeutic approach.

SummaryThis study aimed to verify the effect of peroxiredoxin 1 (PRDX1) in wound healing. PRDX1 and tumor necrosis factor receptor-associated factor 4 (TRAF4) expressions in human umbilical vein endothelial cells (HUVECs) were assessed by real-time quantitative PCR and Western blot. Cell proliferation, migration, and angiogenesis were assessed by cell counting kit-8, wound healing, and tube formation assay. The reactive oxygen species level was measured using 2'-7'-dichlorodihydrofluorescein diacetate. Senescence-associated β-galactosidase staining assay was used to detect cells senescence. The relationship among PRDX1, TRAF4, and UBE3A was determined by co-immunoprecipitation. Upregulation of PRDX1 promoted the proliferation, migration, and angiogenesis of HUVECs. Meanwhile, PRDX1 overexpression inhibited oxidative stress and senescence of HUVECs by H2O2-induced. Furthermore, overexpression of PRDX1 inhibited the degradation of TRAF4 to activate PI3K/AKT/VEGF axis via binding to UBE3A. The effect of PRDX1 on H2O2-induced oxidative stress and senescence was reversed by TRAF4 silence. The promotion of PRDX1 on proliferation, migration, and angiogenesis was canceled by knockdown of TRAF4. PRDX1 inhibited oxidative stress and senescence via restraining the degradation of TRAF4 by binding to UBE3A, eventually accelerating wound healing.

Marine algae are a sustainable and eco-friendly resource, growing rapidly without freshwater or arable land while aiding carbon sequestration. Their extract is rich in biodegradable polysaccharides like alginate, fucoidan, carrageenan, agar, and Ulvan which can be used further in wound healing thanks to their unique characteristics such as ensuring moisture balance and tissue regeneration by forming biocompatible hydrogels with antimicrobial, anti-inflammatory, and antioxidant properties, key requirements in wound healing. The present study explored the utilization of local grown marine algae (i.e., Aegean seashores from Türkiye) and transforming the waste into useful end-products for dermatocosmetics and healing systems. The extracted polyssacharide, e.g., Ulvan which was characterized by means of FT-IR spectroscopy, DSC, and antioxidant activity, was included inside a semi-solid formulation and combined with other polysaccharides from other natural sources such a chitosan, alginate, and hyaluronic acid to form bioactive hydrogels with wound closure activity. The formulated hydrogels exhibited significant swelling capacity, antioxidant activity, and the selected optimal formulation exhibited enhanced wound closure rates in vitro, demonstrating potential for wound-healing applications.

IntroductionWound of diabetic foot ulcers (DFU) is chronic and hard to heal, characterized by impaired inflammatory response, dysfunction of keratinocyte and endothelial cells and improper removal of dying cells. Efferocytosis, as a trigger for phenotype switch of macrophages, plays a critical role in diabetic foot wound healing. Here, we showed the effect of efferocytosis in wound healing of diabetics and identified seven in absentia homolog 2 (SIAH2) as a potential efferocytosis-related biomarker.MethodsBlood and skin samples were collected from 20 patients diagnosed type II diabetes at Qilu Hospital of Shandong University. Efferocytosis related genes in DFU were identified based on GSE147890, GSE80178 datasets as well as RNA-seq data of blood samples. Enrichment analysis, clustering analysis and protein-protein interaction network analysis were conducted based on the efferocytosis related genes in DFU. An array diagram was constructed and survival analysis of DFU was performed based on the associated clinical data. Single-cell sequencing data analysis combined with experiments in vitro, we analyzed the role of SIAH2 in wound healing of DFU as well as its correlation with efferocytosis signal.ResultsOverall efferocytosis and SIAH2 expression level were increased in DFU blood and tissue samples and associated with poor survival in patients. Single-cell analysis revealed elevated SIAH2 expression is positively associated with keratinocyte migration, angiogenesis and efferocytosis of macrophage in wound healing of DFU. SIAH2 involved in efferocytosis-related cell-to-cell communication, especially in “internalization” and “digestion” signals.ConclusionSIAH2 was identified to be one of the key efferocytosis genes and associated with poor prognosis of DFU. Protective upregulation of SIAH2 was involved in angiogenesis, keratinocyte migration and cell-to-cell communication mediated by efferocytosis in DFU wound healing.