The practical application of Fe-N-C catalysts in proton exchange membrane fuel cells is fundamentally constrained by the inherent activity-stability trade-off. Here, we propose a "repair-and-upgrade" engineering strategy that not only repairs pyrolysis-induced defects through carbon and nitrogen supplementation but also evolves conventional FeN4 moieties into stabilized FeN5 configurations via an in situ constructed carbon bilayer. The axial nitrogen modulates the electronic structure of Fe center to enhance catalytic activity, while the adaptive interlayer spacing of the N-linked carbon bilayer compensates for fluctuations in the axial Fe─N bond length during catalysis, therefore anchoring the Fe active sites. When integrated into membrane electrode assemblies, the catalyst delivers a high peak power density of 1221 mW cm-2 and exhibits exceptional durability, retaining over 85% of its initial power density after 10,000 cycles in H2-O2 and showing negligible decay over 45 h at 0.6 V in H2-air tests. This work presents a novel design strategy for stable single-atom catalysts, centered on creating an adaptive local environment that ensures exceptional electrocatalytic stability.
Tympanoplasty repairs tympanic membrane (TM) perforations using grafts. In pediatric patients, cartilage grafts are preferred over fascia due to superior mechanical properties that prevent complications from negative middle ear pressure, including graft failure, retraction, and cholesteatoma formation. However, autologous grafts cause donor-site morbidity and increased surgical time. To overcome these limitations, we engineered an allogeneic porcine meniscus decellularized (MEND) fibrocartilage graft with a unique microchannel structure created by selective elastin and vascular digestion to promote host cell invasion and integration. We evaluated MEND in a rat TM acute perforation model, comparing outcomes to autologous cartilage and fascia grafts, the current clinical standards of care. TMs were monitored via otoendoscopy through 4 weeks, then analyzed by histology and immunohistochemistry. MEND and auricular cartilage grafts successfully closed perforations by day 3, outperforming fascia grafts which frequently dislodged due to poor mechanical integrity. However, unlike cartilage grafts, MEND fully remodeled by day 28, providing superior graft closure and tissue integration compared to both traditional materials. These findings demonstrate MEND's potential as an off-the-shelf solution for pediatric tympanoplasty.
Patients with bone fractures commonly experience an exasperating and long-lasting pain following orthopedic procedures. Spinal monocyte chemotactic protein 3 (MCP-3)-encoding astrogliosis and mGluR5-mediated excitatory synaptic plasticity are essential for central nociceptive transmission. Recent studies highlight the requirement of 7-dehydrocholesterol reductase (DHCR7) for cholesterol overload and neuroinflammation. This present study investigates the potential associations among DHCR7, MCP-3 and mGluR5 in chronic pain using a mouse model of tibial fracture with intramedullary pinning. Here, we report that tibial fracture and orthopedic repairs induce persistent mechanical and cold allodynia, along with spinal cholesterol accumulation and increased expression of DHCR7. Spinal (intrathecal) therapies with DHCR7 inhibitor AY9944 prevent and ameliorate persistent pain after fracture surgeries. Moreover, AY9944 reduces spinal cholesterol overload, MCP-3 secretion, astrocyte activation and increased expression of mGluR5 in fracture mice. Spinal administration of mGluR5 antagonist MPEP is protective against fracture-associated allodynia by decreasing ERK phosphorylation. Strikingly, AY9944 caused the attenuation of behavioral allodynia and astrocyte activation were eliminated after exogenous MCP-3 co-administration. Additionally, spinal neutralization of MCP-3 relieved persistent pain behaviors, astrocyte activation and increased expression of mGluR5 following fractures. Astrocytic inhibitor fluorocitrate reduced chronic fracture pain. Collectively, these findings uncover that spinal DHCR7-mediated cholesterol overload is an important pathogenesis of fracture-associated chronic allodynia by modulating MCP-3-dependent astrocyte activation, mGluR5 expression and ERK phosphorylation.
Macrophages are central regulators of skeletal muscle regeneration, dynamically transitioning from pro-inflammatory (M1-like) to reparative (M2-like) phenotypes to coordinate debris clearance, inflammation modulation, satellite cell activation, and tissue remodeling. This review details the underlying molecular mechanisms, focusing on metabolic reprogramming, such as the shift to oxidative phosphorylation and key roles of AMPK, lactate, and glutamine metabolism. It further examines the transcriptional networks (e.g., PPARγ, Nfix) and multicellular crosstalk that shape the regenerative niche. We analyze macrophage dysfunction in pathological contexts: aging-related impairments in dynamics and metabolism that hinder repair, and in Duchenne Muscular Dystrophy (DMD), where sustained inflammation and trained immunity drive fibrosis. Current challenges include deciphering macrophage heterogeneity beyond the M1-like/M2-like paradigm and bridging translational gaps between models and human disease. The review outlines therapeutic strategies to reprogram macrophage function, spanning pharmacological agents (AMPK/PPARγ agonists, cytokine/chemokine modulation), nanotechnology, cell therapies (e.g., exosomes), and physical interventions. A key feature is the integration of molecular docking analyses, revealing structural interactions between compounds (e.g., AICAR, Cenicriviroc) and targets like AMPK, PPARγ, CCR2, and CCR5. This provides a structural pharmacology foundation for developing targeted immunometabolic therapies to restore muscle regeneration in injury and degenerative diseases.
This study aimed to investigate events related to proximal anastomosis after acute aortic dissection surgery. We analyzed the data of 119 consecutive patients with Stanford type A aortic dissection who underwent emergency surgery at our hospital between October 2015 and March 2023. All patients underwent proximal anastomosis with felt strips and biologic glue reinforcement. Among these, 18 patients (15%) experienced events related to the proximal anastomosis: 14 (12%) had residual dissection in the aortic root, and 4 (3%) had pseudoaneurysms in the aortic root after surgery. We compared the clinical course between the 18 patients with proximal anastomotic events and the other 101 patients. The primary endpoint was all-cause mortality, and the secondary endpoint was redo open-heart surgery. No significant differences were observed in preoperative and procedural characteristics. The incidence of redo open-heart surgery showed a significant difference between the two patient groups (p = 0.0015); however, all-cause mortality showed no significant difference (p = 0.51). The clinical course was different between patients with residual aortic root dissections and those with proximal anastomotic pseudoaneurysms. Residual aortic root dissections were detected via postoperative computed tomography within 1 month and followed-up conservatively owing to the absence of worsening signs. All proximal anastomotic pseudoaneurysms were detected suddenly in the late postoperative phase and presented prompt worsening. All such cases underwent successful redo surgery with patch repair. At reopening, the anastomosis appeared completely detached and nearly ruptured in all cases. Patients with proximal anastomotic events required redo open-heart surgery significantly more frequently. Patients with residual aortic root dissections and those with proximal anastomotic pseudoaneurysms showed a different clinical course. Residual aortic root dissection was associated with insufficient proximal anastomotic repair because it manifested just after surgery. In contrast, proximal anastomotic pseudoaneurysm occurs suddenly in the late phase and shows prompt worsening, thereby requiring acute repair.
To compare the effects of single antiplatelet (SAPT), dual antiplatelet (DAPT), and anticoagulation plus antiplatelet (AC + AP) therapies on branch vessel patency and bleeding risk after branched endovascular aortic repair (B-EVAR). This single-center retrospective cohort study included 250 patients with 880 target branches who underwent B-EVAR (2015-2025). Primary outcomes were branch patency loss (occlusion/stenosis requiring reintervention) and major bleeding (ISTH criteria). Propensity score weighting and competing risk regression controlled confounding. During median 18-month follow-up, 82 branches (9.3%) lost patency: 12.0% (SAPT), 7.0% (DAPT), 7.5% (AC + AP). DAPT significantly improved patency vs. SAPT (sHR 0.72, p = 0.045). Major bleeding occurred in 22 patients (8.8%): 4.4% (SAPT), 7.5% (DAPT), 22.5% (AC + AP). AC + AP tripled bleeding risk (HR 3.10, p = 0.001); DAPT showed non-significant trend (HR 1.62, p = 0.13). DAPT provided the most favorable balance between branch vessel patency and major bleeding after B-EVAR. AC + AP was associated with substantially higher bleeding and should be reserved for patients with an independent indication for anticoagulation. Taken together with prior multicenter European and US consortium data, these findings support a class IB-level preference for DAPT in patients without competing anticoagulation needs; prospective randomized multicenter trials are needed to support a class IA recommendation.
Although endovascular techniques dominate the treatment of abdominal aortic aneurysms (AAAs), open aortic repair (OAR) remains essential for selected patients. As previous research has focused primarily on procedure specific hospital volume for infrarenal AAA repair, this study evaluated whether hospital volume of cumulated non-cardiac open aortic procedures is associated with in hospital mortality and peri-operative outcomes after infrarenal OAR for intact AAA (iAAA). This study was a retrospective nationwide secondary data analysis based on German hospital episode statistics (diagnosis related group [DRG] data) covering the years 2010 to 2023. All hospitals performing non-cardiac open aortic procedures were included and were stratified into quartiles according to their annual volume of all non-cardiac open aortic procedures. A predefined subcohort of cases undergoing open infrarenal repair for iAAA was analysed. The primary outcome was in hospital mortality; secondary outcomes included acute myocardial infarction, acute kidney injury, acute peripheral ischaemia, and mesenteric thrombosis or embolism. Associations were assessed using multivariable multilevel logistic regression analysis adjusted for age, sex, Elixhauser comorbidity score, and treatment in vascular surgery departments with random intercepts for hospital and year. Among 100 137 non-cardiac open aortic procedures, 34 100 cases involved infrarenal OAR for iAAA. Overall, in hospital mortality was 5.9%, ranging from 11.3% in Q1 to 5.2% in Q4. In multivariable analysis, treatment in lower volume hospitals was associated with higher mortality (Q1 vs. Q4: odds ratio [OR] 1.79, 95% confidence interval [CI] 1.30 - 2.47; p < .001). Treatment in vascular surgery departments was associated with reduced mortality (OR 0.83, 95% CI 0.72 - 0.94; p = .005). Higher hospital volume of all non-cardiac open aortic procedures was associated with lower in hospital mortality after infrarenal OAR for iAAA. These findings support centralisation efforts and suggest that minimum case volume requirements should consider the overall non-cardiac open aortic caseload rather than infrarenal procedures alone.
Chronic wounds, such as diabetic ulcers, represent a substantial clinical difficulty because of impaired healing, often resulting from vascular and nerve damage associated with hyperglycemia. Traditional treatments primarily offer supportive care but frequently fail to fully restore tissue function, highlighting the urgent need for advanced regenerative strategies. Stem cell-based therapies, especially those leveraging secretome and exosomes, have gained attention as effective alternatives to direct stem cell transplantation. These cell-free approaches offer several advantages, including low immunogenicity, reduced risk of tumour formation, and greater ease of production, handling, and storage. Secretome and exosomes facilitate wound healing by modulating inflammation, promoting angiogenesis, aiding extracellular matrix remodelling, and stimulating the migration and proliferation of skin cells. Exosomes are vital for intercellular communication, delivering key regenerative signals that trigger anti-inflammatory responses and neovascularisation. Photobiomodulation (PBM), a non-invasive technique using specific light wavelengths, further enhances stem cell function and boosts the therapeutic impact of their secretome by influencing gene and protein expression. When combined, PBM and stem cell-derived secretome or exosomes offer a powerful treatment approach for chronic wound repair by activating critical biological pathways involved in regeneration of damaged tissue. This review highlights the current research on the roles of stem cell secretome, exosomes, and PBM in chronic wound treatment, with a focus on their synergistic mechanisms and promising therapeutic potential.
This prospective open-label comparative study evaluated the efficacy of various conservative treatments for acute anal fissure (AAF) in accelerating epithelialization and reducing pain. A total of 120 patients with symptom duration ≤6 weeks were randomized into four groups: control (hygiene only), dietary therapy (fiber-rich diet + psyllium), monotherapy with a sphincter relaxant (0.2% nitroglycerin ointment), and combined therapy (diet + nitroglycerin). The primary outcome was time to complete epithelialization; secondary outcomes included pain dynamics on the Visual Analog Scale (VAS) and incidence of chronic fissure. Results demonstrated that combined therapy achieved the shortest epithelialization time (10.5±1.5 days), which was significantly shorter than both monotherapy groups and the control (p<0.01). The combined regimen also produced the most pronounced pain reduction from day 3 onward and completely prevented the development of chronic fissure. Dietary modification and nitroglycerin alone improved outcomes but were inferior to the combined approach. In conclusion, the combination of dietary intervention and topical nitroglycerin represents the most effective conservative strategy for AAF, promoting faster healing, superior pain control, and prevention of chronicity.
Bone fracture healing requires coordinated regulation of osteogenesis, angiogenesis, and immune homeostasis within a dynamically evolving microenvironment. However, current biomaterials rarely integrate these three regulatory dimensions. Herein, we engineered L-arginine-loaded zeolitic imidazolate framework-8 (L-Arg@ZIF-8) nanoparticles to remodel the immune-osteogenic-angiogenic microenvironment and accelerate fracture healing. L-Arg@ZIF-8 nanoparticles exhibited uniform morphology, positive surface charge, and stable L-Arg incorporation, enabling efficient cellular uptake and sustained bioactivity. Using two physiologically relevant 3D co-culture spheroid models (osteoblast-macrophage and osteoblast-endothelial), we demonstrated that L-Arg@ZIF-8 promotes osteogenic differentiation, endothelial activation and the upregulation of angiogenic markers, and strengthens osteogenesis-angiogenesis coupling. Bulk transcriptomic profiling further revealed activation of regenerative pathways, including PI3K-Akt and Wnt signaling, along with coordinated modulation of cytokine-receptor interactions and immune-related remodeling programs. In vivo, L-Arg@ZIF-8 markedly accelerated fracture repair in a rat rib fracture model, characterized by enhanced callus formation, increased bone mineral density, greater trabecular thickness, and a significantly elevated mineral apposition rate. Histological and immunofluorescence analyses confirmed upregulation of key osteogenic markers (OPN, OSX) at the fracture site. Together, these findings demonstrate that L-Arg@ZIF-8 functions as a bioengineered microenvironment-modulating nanoplatform that orchestrates immune regulation, osteogenesis, and angiogenesis to promote efficient fracture healing. This strategy offers a promising therapeutic avenue for translational management of complex fractures.
Hypoxic-ischemic encephalopathy is a major cause of neonatal disability and mortality. Its core pathology involves extensive neuronal apoptosis and persistent inflammatory responses. Microglia play a crucial role in maintaining brain homeostasis and promoting injury repair by recognizing and clearing apoptotic neurons. However, the regulatory mechanisms underlying this process remain unclear. This study employed a co-culture model of apoptotic neurons, phagocytic function assays, cytokine analysis, transcriptome sequencing, Gas6 gene knockout and rescue experiments, combined with a mouse model of hypoxic-ischemic brain injury, to elucidate the role of microglia in the phagocytic process and the regulatory function of Gas6. Injured neurons induced an early phase of pro-inflammatory activation and enhanced phagocytic capacity in microglia, followed by a shift towards an anti-inflammatory function. Transcriptome analysis suggested that co-culture with injured neurons activated pathways such as PI3K-AKT and NF-κB in microglia, concomitant with a significant upregulation of Gas6. Furthermore, we found that Gas6 deficiency significantly reduced the phosphorylation level of TAM receptors, leading to impaired downstream PI3K/AKT activation and a marked decrease in Rac1-GTP, thereby suppressing cytoskeletal rearrangement and phagocytic function. In parallel, Gas6-deficient microglia exhibited a sustained pro-inflammatory response, with both their efferocytic capacity and ability to regulate inflammation being significantly compromised. In vivo experiments showed that Gas6-KO mice displayed more severe neurological deficits, increased neuronal apoptosis, and stronger inflammatory responses after HIE. Supplementation with exogenous Gas6 elevated TAM receptor phosphorylation and the PI3K/AKT-Rac1 signaling pathway, partially restoring the phagocytic capacity of microglia. This study demonstrates the important role of the Gas6-TAM-PI3K/AKT-Rac1 signaling axis in modulating microglial efferocytic function and inflammatory state transition. It provides a potential therapeutic strategy for improving HIE prognosis by targeting the regulation of microglial phagocytosis.
This review explores the role of in vitro electrical and mechanical stimulation in modulating wound-healing behavior, with a primary focus on the predominant skin cell types: fibroblasts and keratinocytes. By analyzing the existing literature, we delineate the complex relationships between stimulation parameters-such as voltage, current, frequency, and mechanical strain-and cellular responses, including proliferation and migration. Our data-driven approach compiled more than 390 experimental data points for electrical stimulation and over 170 for mechanical stimulation in vitro, constructing a comprehensive library of cell responses that were previously fragmented and difficult to compare across studies. We critically evaluate various stimulation platforms and configurations, emphasizing their influence on cellular mechanobiology and their translational potential in regenerative medicine. Ultimately, this review underscores the necessity of a multi-parameter optimization strategy to effectively exploit electromechanical cues for targeted skin tissue regeneration.
Leiomyosarcoma (LMS) is characterized by inherent resistance to immune checkpoint blockade, with no conclusive evidence supporting the efficacy of programmed death-1 (PD-1)/programmed death-ligand 1 inhibitor, and it is generally classified as a nonimmunogenic sarcoma subtype. This study analyzed the therapeutic efficacy of temozolomide (TEM)-based regimens in patients with advanced LMS and evaluated pathological changes after TEM treatment to explore the potential role of immunotherapies and the mechanisms that could enhance immunotherapy sensitivity after TEM treatment. This retrospective review included patients with advanced LMS treated at the Cancer Hospital, Chinese Academy of Medical Sciences, and Peking Union Medical College. All patients initiated TEM-based treatments between September 2018 and December 2024. We evaluated patients with advanced LMS and available pathological data before and after TEM-based therapy and those who received subsequent immunotherapy. In total, 47 patients received anthracycline combined with TEM, and 18 patients received gemcitabine combined with TEM. Overall median progression-free survival (mPFS) was 10.0 months, whereas median overall survival (mOS) was 31.0 months. Among six patients who received subsequent PD-1-based immunotherapy after TEM-containing regimens, mPFS and mOS were 13.0 and 45.0 months, respectively. O6-methylguanine DNA methyltransferase negativity tended to be associated with improved survival. Post-TEM biopsies revealed dynamic changes in mismatch repair gene expression, tertiary lymphoid structure counts, and the combined positive score. TEM-based regimens are effective for advanced LMS. Furthermore, pathological changes observed after TEM treatment suggest potential modulation of the tumor microenvironment, supporting further investigation into the integration of immunotherapies in this setting.
The comparative effectiveness of chlorhexidine gluconate (CHG) versus povidone-iodine (PVI) for preventing surgical site infections (SSIs) remains unclear across surgical types and resource settings. This study compared CHG and PVI overall and within key clinical subgroups. Five databases were searched through February 2025 for randomized controlled trials comparing CHG with PVI and reporting SSI outcomes. Random-effects models generated pooled odds ratios (ORs) with 95% confidence intervals (CIs). Twenty-nine RCTs involving 35,317 patients were included. CHG significantly reduced superficial incisional SSIs (OR = 0.80; 95% CI 0.67-0.95; p = 0.01; I2 = 18.4%), but not overall, deep, or organ/space infections; meta-regression indicated that patient age was a significant effect modifier. In cesarean sections, CHG lowered overall (OR = 0.64; 95% CI 0.48-0.85), superficial (OR = 0.65; 95% CI 0.48-0.87), and deep incisional SSIs (OR = 0.41; 95% CI 0.22-0.75). In abdominal surgery, CHG reduced only superficial incisional SSIs (OR = 0.68; 95% CI 0.52-0.91). No significant differences were observed in gynecologic, cardiothoracic, or orthopedic procedures. By wound classification, CHG had no effect in clean surgery but reduced superficial incisional SSIs in clean-contaminated cases (OR = 0.65; 95% CI 0.48-0.89). By income level, no differences were seen in high-income countries, while in low- and middle-income countries CHG decreased overall (OR = 0.58; 95% CI 0.46-0.74), superficial (OR = 0.54; 95% CI 0.38-0.76), and deep incisional SSIs (OR = 0.48; 95% CI 0.25-0.92). Alcohol-based CHG and alcohol-based PVI are comparably effective in most surgical settings. However, CHG demonstrates superior prevention of SSIs in cesarean, abdominal, and clean-contaminated surgeries, with the most substantial benefit in low- and middle-income settings. Broader use may be justified pending cost-effectiveness evaluation.
The perineal membrane (PM), perineal body, and levator ani muscles form the perineal complex, which is responsible for hiatal closure. Yet failures in its connective tissues that may lead to hiatal closure impairment are poorly understood. We tested the hypothesis that pelvic organ prolapse involves PM abnormalities by comparing PM morphology between young women with prolapse and parous controls using a validated MRI-based reconstruction and analysis technique. This is a secondary analysis of MRIs from two prior studies. The PM was traced on coronal scans in 3D Slicer®, and surface models were analyzed using Rhino®. Six PM parameters were measured: swinging door angle, visible bony origin length, hiatal anteroposterior diameter and area, PM surface area, and midline separation. Group comparisons used t tests, with Cohen's d, correlations, and stepwise regression analysis. Resting MRIs from 17 young parous women (aged < 40 years) with prolapse and 20 parous controls were compared. Women with prolapse showed 23% greater midline separation of the PM, 30% larger hiatal area, 26% larger hiatal anteroposterior diameter, 17% longer bony origin, and 26% larger PM surface area (all p ≤ 0.002, d = 1.1-1.6); swinging door angle was similar between groups (p = 0.60). Levator ani status, midline separation, and PM surface area independently predicted prolapse, explaining 76% of variance. The PM structure was altered in those with prolapse through loss of central PM connection, hiatal elongation, and hiatal widening. Larger studies are needed to confirm and guide targeted repair techniques that could potentially prevent prolapse development and/or progression.
Management of rectourinary fistula (RUF) is challenging due to limited data and variability in presentation and treatment. We conducted a systematic review of radical prostatectomy (RP)-related RUF to assess clinical features, diagnostics, treatments, and outcomes, and to propose a structured algorithm to guide management. We conducted a systematic review in accordance with PRISMA guidelines to evaluate the clinical presentation, diagnostic strategies, management approaches, and outcomes of RUF following RP. A comprehensive search of PubMed, Embase, and Web of Science was performed from database inception to January 2025. Data were extracted on patient demographics, symptoms, diagnostic modalities, management strategies, surgical repair techniques and treatment outcomes. A total of 455 cases of RUF following RP were identified across 34 studies. The reported incidence of RUF ranged from <0.01% to 1.5%. The most frequent presenting symptoms were urine leakage per rectum (60.7%), fecaluria (44.1%), and pneumaturia (50.0%). Fecal and/or urinary diversion was utilized in over 60% of cases, with a median stoma duration of 3 months and an indwelling urinary catheter duration of 1 month. Conservative management (observation, fluid replacement and antibiotic therapy) was attempted in a minority of patients and was generally associated with success rates below 50%. Surgical repair was performed in nearly all cases, with the transperineal and transsphincteric approaches being the most commonly employed techniques. The median time to fistula closure ranged from 0.5 to 30 months, with reported surgical success rates varying between 41% and 100%. We propose a management flowchart based on our clinical experience, outlining the diagnostic and therapeutic approach to rectal injury and RP-related RUF. RUF after RP remains a challenging complication, often requiring stepwise management. Conservative treatments rarely succeed, and surgery is often necessary. Our proposed algorithm aims to standardize the approach to RI and RUF, guiding treatment decisions and improving outcomes.
Patients with Alzheimer's disease (AD) exhibit muscle decline and physical compromise. Probiotic supplements may mitigate muscle decline and physical impairment; however, empirical investigations remain limited. We hypothesized that probiotics improve muscle strength and physical performance by repairing intestinal leak in AD patients. We conducted a randomized, double-blind, monocenter trial of AD patients receiving either a placebo (n = 54, 68-84 years old) or a probiotic (Vivomixx 112 billion*, one capsule daily, n = 51, 72-84 years old) for four months. We measured handgrip strength (HGS), body composition, the Short Physical Performance Battery (SPPB), and plasma zonulin, a marker of intestinal permeability, in patients with AD at baseline and after 4 months. Four months of probiotic supplementation improved HGS, gait speed, and total SPPB scores, accompanied by reduced plasma zonulin (all p < 0.05). Patients with sarcopenia or reduced physical capacity (SPPB≤8) exhibited higher zonulin levels. Plasma zonulin was negatively associated with HGS, gait speed, and SPPB scores in univariate analyses (all p < 0.05). Multivariate models adjusting for age, cognition, body mass index, and nutritional status confirmed independent associations of zonulin with functional performance, particularly HGS and gait speed. Probiotics also reduced circulating markers of inflammation and oxidative stress. These results are derived from a male‑only cohort and may not be directly generalizable to female patients. Collectively, probiotics improve HGS and physical capacity by strengthening the intestinal barrier and reducing systemic inflammation and oxidative stress. Further studies should investigate the relative molecular and cellular mechanisms.
This study evaluated the biocompatibility of small extracellular vesicles (sEVs) derived from human umbilical cord mesenchymal stem cells (hUCMSC) loaded in gelatin methacryloyl hydrogel microspheres (sEVs@GM-MS), and examined their effects on the proliferation and migration of human dental pulp stem cells (hDPSCs)/human umbilical vein endothelial cells (HUVECs), as well as their capacity to promote endothelial cell tube formation. Pulpotomy in a rat molar model was used to assess sEVs@GM-MS as a potential pulp-capping agent. sEVs@GM-MS were prepared and physicochemically characterized. In vitro assessments included live/dead staining, Cell Counting Kit-8 (CCK-8), migration assay and tube formation assay. In vivo, 7 and 14 days after pulpotomized with sEVs@GM-MS, GM-MS, iroot BP or without any pulp capping material, rat molars were evaluated using hematoxylin and eosin (H&E), Masson's trichrome, and immunohistochemical (IHC) staining. GM-MS exhibited a porous surface via scanning electron microscopy. PKH67-labeled sEVs@GM-MS showed sustained release of sEVs. The cell proliferation, migration, tube formation in the sEVs@GM-MS group were significantly enhanced compared with those of the NC and GM-MS groups (p < 0.05). In rat pulpotomy model, sEVs@GM-MS group exhibited significant cell proliferation, angiogenesis, and reparative dentinogenesis with immunocytochemical localization of PCNA, CD31 and DMP-1 compared to NC and GM-MS groups (p < 0.05). Compared with the BP group, the sEVs@GM-MS group showed no significant difference in DMP-1 positive expression (p > 0.05). sEVs@GM-MS demonstrated excellent biocompatibility, sustained hUCMSC-sEV release, and enhanced pulp/dentin repair and regenaration, highlighting their potential as a pulp-capping agent.
5-Fluorouracil (5-FU) is a widely utilized antimetabolite in colorectal cancer chemotherapy, primarily exerting its cytotoxic effects by irreversibly inhibiting thymidylate synthase (TS). This inhibition leads to a reduction in deoxythymidine monophosphate (dTMP), which disrupts DNA synthesis and repair. A major challenge in 5-FU treatment is the dose-limiting toxicity of chemotherapeutic-induced intestinal mucositis. Da-Bu-Pi Decoction (DBPD), a well-established formula in traditional Chinese medicine for treating spleen-stomach deficiency, is often used to enhance spleen qi and balance the middle jiao. While growing clinical evidence points to the therapeutic benefits of DBPD in alleviating 5-FU-induced mucositis, the underlying molecular mechanisms remain largely undefined. To elucidate the molecular mechanisms underlying chemotherapy-induced intestinal mucositis (CIM) induced by 5-FU, with a focus on the disruption of bile acid metabolism and the downregulation of the key detoxifying enzyme DPYD expression. DBPD was administered orally to C57BL/6 mice with 5-FU-induced intestinal mucositis over a seven-day period. The evaluation of intestinal damage included assessments of diarrhea, morphology, intestinal barrier function and inflammatory factors, alongside techniques such as immunofluorescence, immunohistochemistry, transmission electron microscopy and Western blot. Transcriptome analysis of mouse ileal tissue was applied to reveal differentially expressed genes (DEGs) in different treated mice, and bile acid metabolism-related genes (UDP-glucuronosyltransferase 1A1 (UGT1A1), UGT1A9, Farnesoid x receptor (FXR), TGR5) and DPYD, a key detoxification enzyme for 5-FU, were confirmed by qRT-PCR. Additionally, changes of DCA and LCA were measured using ELISA. Bioinformatics helped delineate the association of these genes with pan-cancer versus normal tissues. Meanwhile, 5-FU-induced intestinal epithelial cells (HIEC) were treated with serum containing DBPD. It was further explored how DBPD modulates the UGT1A1/TGR5/FXR signaling pathway and enhances DPYD activity to reduce apoptosis and intestinal barrier damage in 5-FU induced HIEC. AlphaFold3 and further bioinformatics analysis predicted the binding interactions and expression correlations among UGT1A1, UGT1A9 and FXR. DBPD is protective by reducing inflammation and intestinal barrier dysfunction in 5-FU-induced intestinal mucositis. Transcriptome analysis and in vivo validation highlighted the crucial function of bile acid metabolism-related pathways and DPYD in 5-FU-induced CIM. 5-FU increased the levels of deoxycholic acid (DCA) and lithocholic acid (LCA) in the mouse ileum. DBPD activated the UGT1A1/TGR5/FXR pathway and up-regulated DPYD to suppress the pathological accumulation of these specific cytotoxic bile acids within the local intestinal microenvironment and ameliorate 5-FU-induced CIM. It was indicated by the analysis of bioinformatics that low levels of UGT1A1, UGT1A9, and FXR exhibited a connection with poor prognosis within colorectal cancer. In vitro studies confirmed that DBPD significantly improved the UGT1A1/TGR5/FXR pathway and increased the expression of DPYD in 5-FU treated HIEC, thereby improving intestinal barrier integrity and alleviating apoptosis. Further validation using the FXR inhibitor (Gly-β-MCA) showed that DBPD ameliorated Gly-β-MCA induced HIEC apoptosis and barrier attenuation. Finally, AlphaFold3 and bioinformatics predictions suggested potential binding interactions between UGT1A1, UGT1A9 and FXR with positively correlated expression.
Glioblastoma is an aggressive primary brain tumor marked by rapid growth, invasiveness, poor prognosis, and an over 90 % tumor recurrence rate. Current radiation and chemotherapy treatments are limited by non-selectivity and toxicity, creating a need for safer complementary treatments. Historically, natural health products (NHPs) have been used medicinally across cultures for their anti-inflammatory and antioxidant effects. More recently, they have gained recognition for their selective, non-toxic properties in cancer treatment, suggesting their potential as adjuncts to conventional therapies. Black maitake (Grifola frondosa) extract, a well-tolerated NHP with known immunomodulatory properties, has demonstrated anticancer effects in breast cancer models. This study investigates the ability of Black Maitake Odaira Extract - Prothera (BMOE; a trade name of the extract manufactured by Shogun Maitake Canada, London, ON) to induce cell death in the U-87 MG glioblastoma cell line using 2D and 3D models, alone and in combination with the standard chemotherapy: temozolomide (TMZ). Apoptosis was assessed via Hoechst 33,342, annexin V, and propidium iodide staining, along with morphological analyses. Mitochondrial depolarization was measured using TMRM, cell migration was assessed via wound-healing assays, and structural integrity was evaluated using 3D spheroids. BMOE, alone and with TMZ, induced dose-dependent apoptosis, mitochondrial depolarization, and impaired glioblastoma cell migration. BMOE also disrupted 3D spheroid structures and promoted nuclear condensation, consistent with apoptotic processes. Most notably, BMOE significantly enhanced the anti-cancer effects of TMZ. These findings support the potential of BMOE as a complementary therapy that enhances the efficacy of current glioblastoma treatments.