A highly stretchable smart dressing for wound infection monitoring and treatment.

Smart dressings integrated with bioelectronics have attracted considerable attention and become promising solutions for skin wound management. However, due to the mechanical distinction between human body and the interface of electronics, previous smart dressings often suffered obvious degradation in electrical performance when attached to the soft and curvilinear wound sites. Here, we report a stretchable dressing integrated with temperature and pH sensor for wound status monitoring, as well as an electrically controlled drug delivery system for infection treatment. The wound dressing was featured with the deployment of liquid metal for seamless connection between rigid electrical components and gold particle-based electrodes, achieving a stretchable soft-hard interface. Stretching tests showed that both the sensing system and drug delivery system exhibited good stretchability and long-term stable conductivity with the resistance change rate less than 6 % under 50 % strain. Animal experiments demonstrated that the smart dressing was capable of detecting bacterial infection via the biomarkers of temperature and pH value and the infection factors of wound were significantly improved with therapy through electrically controlled antibiotics releasing. This proof-of-concept prototype has potential to significantly improve management of the wound, especially those with dynamic strain.

3D Bioprinting of Artificial Skin Substitute with Improved Mechanical Property and Regulated Cell Behavior through Integrating Patterned Nanofibrous Films.

Three-dimensional (3D) bioprinting has advantages for constructing artificial skin tissues in replicating the structures and functions of native skin. Although many studies have presented improved effect of printing skin substitutes in wound healing, using hydrogel inks to fabricate 3D bioprinting architectures with complicated structures, mimicking mechanical properties, and appropriate cellular environments is still challenging. Inspired by collagen nanofibers withstanding stress and regulating cell behavior, a patterned nanofibrous film was introduced to the printed hydrogel scaffold to fabricate a composite artificial skin substitute (CASS). The artificial dermis was printed using gelatin-hyaluronan hybrid hydrogels containing human dermal fibroblasts with gradient porosity and integrated with patterned nanofibrous films simultaneously, while the artificial epidermis was formed by seeding human keratinocytes upon the dermis. The collagen-mimicking nanofibrous film effectively improved the tensile strength and fracture resistance of the CASS, making it sewable for firm implantation into skin defects. Meanwhile, the patterned nanofibrous film also provided the biological cues to guide cell behavior. Consequently, CASS could effectively accelerate the regeneration of large-area skin defects in mouse and pig models by promoting re-epithelialization and collagen deposition. This research developed an effective strategy to prepare composite bioprinting architectures for enhancing mechanical property and regulating cell behavior, and CASS could be a promising skin substitute for treating large-area skin defects.

Accurate Density Prediction of Sesquiterpenoid HEDFs and the Multiproperty Computing Server SesquiterPre.

Accurate and rapid evaluation of density is crucial for evaluating the packing and combustion characteristics of high-energy-density fuels (HEDFs). This parameter is pivotal in the selection of high-performance HEDFs. Our study leveraged a polycyclic compound density data set and quantum chemical (QC) descriptors to establish a correlation with the target properties using the XGBoost algorithm. We utilized a recursive feature elimination method to simplify the model and developed a concise and interpretable density prediction model incorporating only six QC descriptors. The model demonstrated robust performance, achieving coefficients of determination (R 2) of 0.967 and 0.971 for internal and external test sets, respectively, and root-mean-square errors (RMSE) of 0.031 and 0.027 g/cm3, respectively. Compared to the other two mainstream methods, the marginal discrepancy between the predicted and actual molecular densities underscores the model's superior predictive ability and more usefulness for energy density calculation. Furthermore, we developed a web server (SesquiterPre, https://sespre.cmdrg.com/#/) that can simultaneously calculate the density, enthalpy of combustion, and energy density of sesquiterpenoid HEDFs, which greatly facilitates the use of researchers and is of great significance for accelerating the design and screening of novel sesquiterpenoid HEDFs.

Gelation and Plugging Performance of Low-Concentration Partially Hydrolyzed Polyacrylamide/Polyethyleneimine System at Moderate Temperature and in Fractured Low-Permeability Reservoir.

HPAM/PEI gel is a promising material for conformance control in hydrocarbon reservoirs. However, its use in low-permeability reservoirs is limited by the high polymer concentrations present. In this study, the gelation performance of an HPAM/PEI system with HPAM < 2.0 wt.% was systematically investigated. The gelation time for HPAM concentrations ranging from 0.4 to 2.0 wt.% varied from less than 1 h to 23 days, with the highest gel strength identified as grade H. The hydrodynamic radius manifested the primary effect of HPAM on the gelation performance. Branched PEI provided superior gelation performance over linear PEI, and the gelation performance was only affected when the molecular weight of the PEI varied significantly. The optimal number ratio of the PEI-provided imine groups and the HPAM-provided carboxylic acid functional groups was approximately 1.6:1~5:1. Regarding the reservoir conditions, the temperature had a crucial effect on the hydrodynamic radius of HPAM. Salts delayed the gelation process, and the order of ionic influence was Ca2+ > Na+ > K+. The pH controlled the crosslinking reaction, primarily due to the protonation degree of PEI and the hydrolysis degree of HPAM, and the most suitable pH was approximately 10.5. Plugging experiments based on a through-type fracture showed that multi-slug plugging could significantly improve the plugging performance of the system, being favorable for its application in fractured low-permeability reservoirs.

Radiotherapy and immunology.

The majority of cancer patients receive radiotherapy during the course of treatment, delivered with curative intent for local tumor control or as part of a multimodality regimen aimed at eliminating distant metastasis. A major focus of research has been DNA damage; however, in the past two decades, emphasis has shifted to the important role the immune system plays in radiotherapy-induced anti-tumor effects. Radiotherapy reprograms the tumor microenvironment, triggering DNA and RNA sensing cascades that activate innate immunity and ultimately enhance adaptive immunity. In opposition, radiotherapy also induces suppression of anti-tumor immunity, including recruitment of regulatory T cells, myeloid-derived suppressor cells, and suppressive macrophages. The balance of pro- and anti-tumor immunity is regulated in part by radiotherapy-induced chemokines and cytokines. Microbiota can also influence radiotherapy outcomes and is under clinical investigation. Blockade of the PD-1/PD-L1 axis and CTLA-4 has been extensively investigated in combination with radiotherapy; we include a review of clinical trials involving inhibition of these immune checkpoints and radiotherapy.

Targeting the dendritic cell-secreted immunoregulatory cytokine CCL22 alleviates radioresistance.

PURPOSE: Radiation-mediated immune suppression limits efficacy and is a barrier in cancer therapy. Radiation induces negative regulators of tumor immunity including regulatory T cells (Treg). Mechanisms underlying Treg infiltration after radiotherapy (RT) are poorly defined. Given that dendritic cells (cDC) maintain Treg we sought to identify and target cDC signaling to block Treg infiltration after radiation. EXPERIMENTAL DESIGN: Transcriptomics and high dimensional flow cytometry revealed changes in murine tumor cDC that not only mediate Treg infiltration after RT, but associate with worse survival in human cancer datasets. Antibodies perturbing a cDC-CCL22-Treg axis were tested in syngeneic murine tumors. A prototype interferon-anti-epidermal growth factor receptor fusion protein (αEGFR-IFNα) was examined to block Treg infiltration and promote a CD8+ T cell response after RT. RESULTS: Radiation expands a population of mature cDC1 enriched in immunoregulatory markers that mediates Treg infiltration via the Treg-recruiting chemokine CCL22. Blocking CCL22 or Treg depletion both enhanced RT efficacy. αEGFR-IFNα blocked cDC1 CCL22 production while simultaneously inducing an antitumor CD8+ T cell response to enhance RT efficacy in multiple EGFR-expressing murine tumor models, including following systemic administration. CONCLUSIONS: We identify a previously unappreciated cDC mechanism mediating Treg tumor infiltration after RT. Our findings suggest blocking the cDC1-CCL22-Treg axis augments RT efficacy. αEGFR-IFNα added to RT provided robust antitumor responses better than systemic free interferon administration, and may overcome clinical limitations to interferon therapy. Our findings highlight the complex behavior of cDC after RT and provide novel therapeutic strategies for overcoming RT-driven immunosuppression to improve RT efficacy.

Synchronous supraclavicular vascularized lymph node transfer and liposuction for gynecological cancer-related lower extremity lymphedema: a clinical comparative analysis of three different procedures.

OBJECTIVE: Gynecological cancer-related lower extremity lymphedema (GC-LEL), a chronic, progressive condition, lacks a standardized treatment. Currently, supraclavicular vascularized lymph node transfer (SC-VLNT) is a favored approach in the treatment of lymphedema, and there is a trend toward combination technology. This study conducts a comparative analysis of three techniques for treating GC-LEL with simultaneous SC-VLNT and liposuction. METHODS: A cohort of 35 patients with GC-LEL was examined, comprising 13 patients who underwent single lymph nodes flap with a skin paddle (SLNF+P), 12 who received single lymph nodes flap without a skin paddle (SLNF), and 10 who accepted dual lymph nodes flap without a skin paddle (DLNF). Patient demographics and outcomes were meticulously documented, covering intra- and postoperative variables. RESULTS: The median limb volume reduction were 56.4% (SLNF+P), 60.8% (SLNF), and 50.5% (DLNF) in stage II, and 54.0% (SLNF+P), 59.8% (SLNF), and 54.4% (DLNF) in stage III. DLNF group procedures entailed longer flap harvesting and transplantation times. The SLNF+P group, on average, had an 8-day postoperative hospitalization, longer than others. All patients noted subjective improvements in Lymphedema Quality of Life scores, with lymphoscintigraphy revealing enhanced lymphatic flow in 29 of the 35 cases. A notable decrease in cellulitis incidence was observed. Additionally, the occurrence of cellulitis decreased significantly, except for DLNF (Stage Ⅱ). The median follow-up time was 16 months (range, 12-36 months), with no reported severe postoperative complications. CONCLUSIONS: For advanced GC-LEL, SLNF combined with liposuction is a preferred treatment, offering fewer complications, shorter operative time, and hospitalization.

QuanDB: a quantum chemical property database towards enhancing 3D molecular representation learning.

Previous studies have shown that the three-dimensional (3D) geometric and electronic structure of molecules play a crucial role in determining their key properties and intermolecular interactions. Therefore, it is necessary to establish a quantum chemical (QC) property database containing the most stable 3D geometric conformations and electronic structures of molecules. In this study, a high-quality QC property database, called QuanDB, was developed, which included structurally diverse molecular entities and featured a user-friendly interface. Currently, QuanDB contains 154,610 compounds sourced from public databases and scientific literature, with 10,125 scaffolds. The elemental composition comprises nine elements: H, C, O, N, P, S, F, Cl, and Br. For each molecule, QuanDB provides 53 global and 5 local QC properties and the most stable 3D conformation. These properties are divided into three categories: geometric structure, electronic structure, and thermodynamics. Geometric structure optimization and single point energy calculation at the theoretical level of B3LYP-D3(BJ)/6-311G(d)/SMD/water and B3LYP-D3(BJ)/def2-TZVP/SMD/water, respectively, were applied to ensure highly accurate calculations of QC properties, with the computational cost exceeding 107 core-hours. QuanDB provides high-value geometric and electronic structure information for use in molecular representation models, which are critical for machine-learning-based molecular design, thereby contributing to a comprehensive description of the chemical compound space. As a new high-quality dataset for QC properties, QuanDB is expected to become a benchmark tool for the training and optimization of machine learning models, thus further advancing the development of novel drugs and materials. QuanDB is freely available, without registration, at https://quandb.cmdrg.com/ .

Identification of a multidrug resistance genomic island harboring a nonfunctional optrA gene in Campylobacter coli of chicken origin.

Campylobacter spp., such as Campylobacter jejuni and Campylobacter coli, are important zoonotic Gram-negative pathogens that cause acute intestinal diseases in humans. In this study, a retrospective analysis was conducted on previously collected Campylobacter isolates from antimicrobial resistance surveillance. A total of 29 optrA-positive C. coli strains were identified and subjected to second-generation sequencing. Multilocus sequence typing and single nucleotide polymorphism analyses demonstrated that the 29 optrA-positive isolates were genetically homogeneous. Notably, among the 29 isolated strains, the ΔoptrA variants exhibit a nonsense mutation at position 979 where the base C is substituted by T, leading to the formation of a premature termination codon. The alignment of sequences and genetic environmental characteristics suggested that ΔoptrA located on a chromosomally carried multidrug-resistant genomic island. There are other resistant genes on the multidrug resistance genomic island, such as aph(2'')-If, aph(3')-III, aadE, tet(O), tet(L), cat, erm(A), optrA and blaOXA-61. As a result, the 29 ΔoptrA-positive strains displayed susceptibility to both florfenicol and linezolid. The ΔoptrA gene is linked to the erm(A) gene, resulting in the formation of translocatable unit (TU) that are encompassed by two copies of IS1216 mobile elements. Multiple occurrences of similar TUs have been documented in numerous C. coli and provided evidence for the significance of TUs in facilitating the transfer of drug resistance genes in C. coli.

Development of a screening system of gene sets for estimating the time of early skeletal muscle injury based on second-generation sequencing technology.

The present study is aimed to address the challenge of wound age estimation in forensic science by identifying reliable genetic markers using low-cost and high-precision second-generation sequencing technology. A total of 54 Sprague-Dawley rats were randomly assigned to a control group or injury groups, with injury groups being further divided into time points (4 h, 8 h, 12 h, 16 h, 20 h, 24 h, 28 h, and 32 h after injury, n = 6) to establish rat skeletal muscle contusion models. Gene expression data were obtained using second-generation sequencing technology, and differential gene expression analysis, weighted gene co-expression network analysis (WGCNA) and time-dependent expression trend analysis were performed. A total of six sets of biomarkers were obtained: differentially expressed genes at adjacent time points (127 genes), co-expressed genes most associated with wound age (213 genes), hub genes exhibiting time-dependent expression (264 genes), and sets of transcription factors (TF) corresponding to the above sets of genes (74, 87, and 99 genes, respectively). Then, random forest (RF), support vector machine (SVM) and multilayer perceptron (MLP), were constructed for wound age estimation from the above gene sets. The results estimated by transcription factors were all superior to the corresponding hub genes, with the transcription factor group of WGCNA performed the best, with average accuracy rates of 96% for three models' internal testing, and 91.7% for the highest external validation. This study demonstrates the advantages of the indicator screening system based on second-generation sequencing technology and transcription factor level for wound age estimation.

Versatile chondroitin sulfate-based nanoplatform for chemo-photodynamic therapy against triple-negative breast cancer.

Versatile nanoplatform equipped with chemo-photodynamic therapeutic attributes play an important role in improving the effectiveness of tumor treatments. Herein, we developed multifunctional nanoparticles based on chondroitin sulfate A (CSA) for the targeted delivery of chlorin e6 (Ce6) and doxorubicin (DOX), in a combined chemo-photodynamic therapy against triple-negative breast cancer. CSA was chosen for its hydrophilic properties and its affinity to CD44 receptor-overexpressed tumor cells. The CSA-ss-Ce6 (CSSC) conjugate was synthesized utilizing a disulfide linker. Subsequently, DOX-loaded CSSC (CSSC-D) nanoparticles were fabricated, showcasing a nearly spherical shape with an average particle size of 267 nm. In the CSSC-D nanoparticles, the chemically attached Ce6 constituted 1.53 %, while the physically encapsulated DOX accounted for 8.11 %. Both CSSC-D and CSSC nanoparticles demonstrated a reduction-sensitive release of DOX or Ce6 in vitro. Under near-infrared (NIR) laser irradiation, CSSC-D showed the enhanced generation of reactive oxygen species (ROS), improving cytotoxic effects against triple-negative breast cancer 4T1 and MDA-MB-231 cells. Remarkably, the CSSC-D with NIR exhibited the most potent tumor growth inhibition in comparison to other groups in the 4T1-bearing Balb/c mice model. Overall, this CSSC-D nanoplatform shows significant promise as a powerful tool for a synergetic approach in chemo-photodynamic therapy in triple-negative breast cancer.

Polymorphisms of IFN signaling genes and FOXP4 influence the severity of COVID-19.

BACKGROUND: The clinical manifestations of COVID-19 range from asymptomatic, mild to moderate, severe, and critical disease. Host genetic variants were recognized to affect the disease severity. However, the genetic landscape differs among various populations. Therefore, we explored the variants associated with COVID-19 severity in the Guangdong population. METHODS: A total of 314 subjects were selected, of which the severe and critical COVID-19 patients were defined as "cases", and the mild and moderate patients were defined as "control". Twenty-two variants in interferon-related genes and FOXP4 were genotyped using the MassARRAY technology platform. RESULTS: IFN signaling gene MX1 rs17000900 CA + AA genotype was correlated with a reduced risk of severe COVID-19 in males (P = 0.001, OR = 0.050, 95%CI = 0.008-0.316). The AT haplotype comprised of MX1 rs17000900 and rs2071430 was more likely to protect against COVID-19 severity (P = 6.3E-03). FOXP4 rs1886814 CC genotype (P = 0.001, OR = 3.747, 95%CI = 1.746-8.043) and rs2894439 GA + AA genotype (P = 0.001, OR = 5.703, 95% CI = 2.045-15.903) were correlated with increased risk of severe COVID-19. Haplotype CA comprised of rs1886814 and rs2894439 was found to be correlated with adverse outcomes (P = 7.0E-04). FOXP4 rs1886814 CC (P = 0.0004) and rs2894439 GA + AA carriers had higher neutralizing antibody titers (P = 0.0018). The CA + AA genotype of MX1 rs17000900 tended to be correlated with lower neutralizing antibody titers than CC genotype (P = 0.0663), but the difference was not statistically significant. CONCLUSION: Our study found a possible association between MX1 and FOXP4 polymorphisms and the severity of COVID-19. Distinguishing high-risk patients who develop severe COVID-19 will provide clues for early intervention and individual treatment strategies.

The TET-Sall4-BMP regulatory axis controls craniofacial cartilage development.

Craniofacial microsomia (CFM) is a congenital defect that usually results from aberrant development of embryonic pharyngeal arches. However, the molecular basis of CFM pathogenesis is largely unknown. Here, we employ the zebrafish model to investigate mechanisms of CFM pathogenesis. In early embryos, tet2 and tet3 are essential for pharyngeal cartilage development. Single-cell RNA sequencing reveals that loss of Tet2/3 impairs chondrocyte differentiation due to insufficient BMP signaling. Moreover, biochemical and genetic evidence reveals that the sequence-specific 5mC/5hmC-binding protein, Sall4, binds the promoter of bmp4 to activate bmp4 expression and control pharyngeal cartilage development. Mechanistically, Sall4 directs co-phase separation of Tet2/3 with Sall4 to form condensates that mediate 5mC oxidation on the bmp4 promoter, thereby promoting bmp4 expression and enabling sufficient BMP signaling. These findings suggest the TET-BMP-Sall4 regulatory axis is critical for pharyngeal cartilage development. Collectively, our study provides insights into understanding craniofacial development and CFM pathogenesis.

Pathological Characteristics and Classification of Unstable Coronary Atherosclerotic Plaques.

Important forensic diagnostic indicators of sudden death in coronary atherosclerotic heart disease, such as acute or chronic myocardial ischemic changes, sometimes make it difficult to locate the ischemic site due to the short death process, the lack of tissue reaction time. In some cases, the deceased died of sudden death on the first-episode, resulting in difficulty for medical examiners to make an accurate diagnosis. However, clinical studies on coronary instability plaque revealed the key role of coronary spasm and thrombosis caused by their lesions in sudden coronary death process. This paper mainly summarizes the pathological characteristics of unstable coronary plaque based on clinical medical research, including plaque rupture, plaque erosion and calcified nodules, as well as the influencing factors leading to plaque instability, and briefly describes the research progress and technique of the atherosclerotic plaques, in order to improve the study on the mechanism of sudden coronary death and improve the accuracy of the forensic diagnosis of sudden coronary death by diagnosing different pathologic states of coronary atherosclerotic plaques.

Radiotherapy Enhances Metastasis Through Immune Suppression by Inducing PD-L1 and MDSC in Distal Sites.

PURPOSE: Radiotherapy (RT) is a widely employed anticancer treatment. Emerging evidence suggests that RT can elicit both tumor-inhibiting and tumor-promoting immune effects. The purpose of this study is to investigate immune suppressive factors of radiotherapy. EXPERIMENTAL DESIGN: We used a heterologous two-tumor model in which adaptive concomitant immunity was eliminated. RESULTS: Through analysis of PD-L1 expression and myeloid-derived suppressor cells (MDSC) frequencies using patient peripheral blood mononuclear cells and murine two-tumor and metastasis models, we report that local irradiation can induce a systemic increase in MDSC, as well as PD-L1 expression on dendritic cells and myeloid cells, and thereby increase the potential for metastatic dissemination in distal, nonirradiated tissue. In a mouse model using two distinct tumors, we found that PD-L1 induction by ionizing radiation was dependent on elevated chemokine CXCL10 signaling. Inhibiting PD-L1 or MDSC can potentially abrogate RT-induced metastasis and improve clinical outcomes for patients receiving RT. CONCLUSIONS: Blockade of PD-L1/CXCL10 axis or MDSC infiltration during irradiation can enhance abscopal tumor control and reduce metastasis.

Extranodal nasal-type NK/T-cell lymphoma with CD20 positive: A case report and review of literature.

ABSTRACT: Extranodal nasal-type natural killer (NK)/T-cell lymphoma is a type of non-Hodgkin lymphoma. Neoplastic lymphocytes are positive for CD4, CD56, and CD20, a specific B-cell marker. CD20 positive NK/T-cell lymphoma is rare, with only nine reported cases. This paper reports a case of nasal-type NK/T-cell lymphoma with CD20 positivity in a 47-year-old woman. The patient presented with bilateral nasal congestion and bloody nasal cavity secretions for 2 months. Computed tomography revealed thickening of the nasal mucosa and posterior wall of the nasopharyngeal crest, and the left and right cervical lymph nodes were enlarged. On histopathology, the lesion was composed of medium-sized atypical lymphoid cells and vascular infringement. Immunohistochemical staining showed that the tumor cells were positive for CD20, CD3, CD56, and Epstein-Barr virus (EBV)-encoded RNA in situ hybridization. The patient was treated with radiotherapy for 2 months and is currently well.

Sulfasalazine promotes ferroptosis through AKT-ERK1/2 and P53-SLC7A11 in rheumatoid arthritis.

OBJECTIVE: Ferroptosis has been reported to play a role in rheumatoid arthritis (RA). Sulfasalazine, a common clinical treatment for ankylosing spondylitis, also exerts pathological influence on the progression of rheumatoid arthritis including the induced ferroptosis of fibroblast-like synoviocytes (FLSs), which result in the perturbated downstream signaling and the development of RA. The aim of this study was to investigate the underlying mechanism so as to provide novel insight for the treatment of RA. METHODS: CCK-8 and Western blotting were used to assess the effect of sulfasalazine on FLSs. A collagen-induced arthritis mouse model was constructed by the injection of collagen and Freund's adjuvant, and then, mice were treated with sulfasalazine from day 21 after modeling. The synovium was extracted and ferroptosis was assessed by Western blotting and immunofluorescence staining. RESULTS: The results revealed that sulfasalazine promotes ferroptosis. Compared with the control group, the expression levels of ferroptosis-related proteins such as glutathione peroxidase 4, ferritin heavy chain 1, and solute carrier family 7, member 11 (SLC7A11) were lower in the experimental group. Furthermore, deferoxamine inhibited ferroptosis induced by sulfasalazine. Sulfasalazine-promoted ferroptosis was related to a decrease in ERK1/2 and the increase of P53. CONCLUSIONS: Sulfasalazine promoted ferroptosis of FLSs in rheumatoid arthritis, and the PI3K-AKT-ERK1/2 pathway and P53-SLC7A11 pathway play an important role in this process.

Chemically Cross-Linked Hammerhead Ribozyme as an Efficient RNA Interference Tool.

RNA-cleaving ribozymes are promising candidates as general tools of RNA interference (RNAi) in gene manipulation. However, compared with other RNA systems, such as siRNA and CRISPR technologies, the ribozyme tools are still far from broad applications on RNAi due to their poor performance in the cellular context. In this work, we report an efficient RNAi tool based on chemically modified hammerhead ribozyme (HHR). By the introduction of an intramolecular linkage into the minimal HHR to reconstruct the distal interaction within the tertiary ribozyme structure, this cross-linked HHR exhibits efficient RNA substrate cleavage activities with almost no sequence constraint. Cellular experiments suggest that both exogenous and endogenous RNA expression can be dramatically knocked down by this HHR tool with levels comparable to those of siRNA. Unlike the widely applied protein-recruiting RNA systems (siRNA and CRISPR), this ribozyme tool functions solely on RNA itself with great simplicity, which may provide a new approach for gene manipulation in both fundamental and translational studies.

Metformin eliminates lymphedema in mice by alleviating inflammation and fibrosis: implications for human therapy.

BACKGROUND: Secondary lymphedema is a chronic, disabling disease impacting over 50% of patients with cancer and lacking effective pharmacological treatment even for early- to mid-disease stages. Metformin reportedly exerts anti-inflammatory and anti-fibrotic effects and is safe, with minimal side effects; We investigated the role of metformin in lymphedema mouse models and examined underlying molecular mechanisms. METHODS: Male C57BL/6 mice (6-8-week-old; n=15/group) received metformin (300 mg/kg/day) by gavage on day 3 after lymphedema surgery; saline and sham groups were administered the same volume of saline. Hindlimb circumference and tail volume were monitored every two days. On day 28, samples were collected for histological assessment, western blotting, and reverse transcription-quantitative PCR analysis of inflammation, fibrosis, and AMPK expression. AMPK activity was assayed in patients with secondary lymphedema (ISL II) and controls following strict inclusion criteria. RESULTS: Compared with the saline group, the metformin group exhibited hindlimb circumference and tail volume reduced by 469.70% and 305.18%, respectively. on day 28. Dermal thickness was reduced by 38.27% and 72.57% in the hindlimbs and tail, respectively. Metformin decreased CD4+ T cell infiltration by 19.73% and expression levels of interleukin (IL)-4, IL-13, IL-17, and transforming growth factor-ß1. Additionally, it lowered collagen I deposition by 33.18%. Compared with the saline group, the number of lymphatic vessels increased by 229.96% in the metformin group. Both the saline group mice and patients with lymphedema showed reduced AMPK activity, while metformin increased p-AMPK expression by 106.12%. CONCLUSION: Metformin alleviated inflammation and fibrosis and increased lymphangiogenesis in lymphedema mouse models by activating AMPK signaling.