Sepsis-induced acute lung injury (ALI) represents a complex and life-threatening condition with limited therapeutic options. Recent research has unveiled the role of methyltransferase-like 3 (METTL3)-mediated N6-methyladenosine (m6A) modifications in exacerbating ferroptosis via m6A-insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2)-dependent mitochondrial metabolic reprogramming, shedding light on potential therapeutic targets. This study delves into the implications, challenges, and prospects of this intricate molecular pathway in sepsis-associated ALI. METTL3-mediated M6A modifications assume a pivotal role in the pathogenesis of sepsis-induced ALI. These modifications exacerbate ferroptosis, a regulated cell death process characterized by iron-dependent oxidative damage to lipids. The involvement of m6A-IGF2BP2-dependent mitochondrial metabolic reprogramming adds another layer of complexity to this mechanism, offering potential therapeutic avenues. Understanding the intricate network of METTL3-mediated m6A modifications, IGF2BP2, and mitochondrial metabolic reprogramming poses a formidable challenge. Developing interventions that modulate this pathway while minimizing off-target effects remains a significant hurdle. Patient-specific responses and identifying reliable biomarkers further complicate the clinical translation of these findings. The unraveling of this molecular pathway holds promise for personalized medicine approaches in ALI management. Early diagnosis and tailored interventions based on individual patient profiles may significantly enhance clinical outcomes. Collaboration among multidisciplinary teams, including researchers, clinicians, and drug developers, is essential to bridge the gap between laboratory discoveries and clinical applications.
Cardiovascular and cerebrovascular diseases are among the leading causes of death worldwide. Development of these diseases occurs following pathological structural remodeling and functional changes in the vascular wall. Emerging evidence suggests that histone acetyltransferases (HATs) play a role in the pathological processes of the arterial wall. However, there is currently a lack of comprehensive reviews examining the role of HATs in vascular diseases. The aim of this research is therefore to systematically describe the pathological effects of various risk factors on different layers of cells in the arterial vascular wall. The risk factors include abnormal activation of the renin-angiotensin system, hyperglycemia, high-sodium diets, and intermittent hypoxia. The effects regulated by HATs involve the nuclear factor kappa-B (NF-κB)-NOD-like receptor family pyrin domain containing 3 (NLRP3) and AMP-activated protein kinase (AMPK) pathways, and the mitogen-activated protein kinase (MAPK) and vascular endothelial growth factor receptor 2 (VEGFR2) signaling pathways. We also explore the dual role of HATs in vascular protection and injury. Additionally, this study focuses on the prospects of future therapeutic strategies targeting HATs, including innovative approaches such as HAT inhibitors, epigenetic degraders, non-coding RNA interventions, and epigenetic editing technologies. The aim of this review is to provide a basis for the development of selective subtype HAT inhibitors.
The utilization of cell-free therapies derived from extracellular vesicles (EVs) has garnered mounting interest as a promising approach to address the myriad challenges associated with ischemic stroke. These Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) possess considerable therapeutic potential due to their inherent properties, including low immunogenicity, efficient cargo transportation, and the ability to cross the blood-brain barrier. This review examines the mechanisms underlying mesenchymal stem cell-derived EVs in the treatment of ischemic stroke. Future research should aim to identify optimal strategies for EV-based interventions, including combination therapy and preconditioning strategies.
Bone remains one of the most hospitable—and devastating—destinations for metastatic cancer cells. At the center of this unwelcome alliance is transforming growth factor‑β (TGF‑β), a cytokine stored in the mineralized matrix and unleashed during osteoclastic bone resorption. Once activated, TGF‑β fuels a self‑reinforcing “vicious cycle”: it co‑opts tumor cells to undergo epithelial‑to‑mesenchymal transition, recruits and primes osteoclasts, suppresses osteoblast function, and shapes an immunosuppressive niche that shields malignant clones. The result is a micro‑environment exquisitely tuned for tumor survival, skeletal destruction, and therapy resistance. This review traces the molecular choreography of TGF‑β signaling within the bone tumor microenvironment (TME), detailing its crosstalk with osteogenic, immune, and stromal compartments across breast, prostate, and lung cancer metastases. We synthesize pre‑clinical and clinical efforts to interrupt this pathway, ranging from ligand-neutralizing antibodies and activin receptor-like kinase 5 (ALK5) kinase inhibitors to antisense oligonucleotides and tumor-selective ligand traps—and examine why benefits observed in early trials are tempered by dose‑limiting toxicities and adaptive resistance. Beyond TGF‑β itself, we highlight parallel targets in the TME, including receptor activator of nuclear factor kappa-B ligand (RANKL)‑driven osteoclastogenesis, vascular endothelial growth factor/fibroblast growth factor (VEGF/FGF)‑mediated angiogenesis, and immune checkpoints such as PD‑1, TIM‑3, and LAG‑3, arguing that multi‑pronged combinations guided by real‑time TME profiling offer the most promising path forward. We outline pressing research priorities: mapping the spatiotemporal dynamics of TGF‑β activation, identifying predictive biomarkers for patient stratification, and engineering bone‑targeted delivery systems that preserve normal tissue repair. By decoding and disrupting the TGF‑β‑centered circuitry of bone metastasis, we can move closer to therapies that not only palliate skeletal complications but also prolong life for patients with advanced cancer.
Tendon–bone healing has always been a difficult point in clinical orthopedics, tissue engineering, and sports medicine. The most important structure for stress transmission is the tendon–bone junction, which is the transition from soft tissue to hard tissue. Biological effects can be produced by a variety of cytokines in different cells. During the remodelling and repair of the tendon–bone junction, the key factor is the inflammatory microenvironment regulated by macrophages through various physiological processes such as autophagy, differentiation, and polarization, which mediate cytokine release and influence other cellular functions. This provides a theoretical basis for the development of new mechanisms for tendon–bone junction repair. This article aims to review the potential role of macrophage autophagy, differentiation, and polarization in the repair of tendon–bone injury. In addition, we propose that future research should integrate multidisciplinary approaches such as molecular biology and bioinformatics to conduct in-depth analyses of the dynamic networks of autophagy and polarization in macrophages, thereby guiding future research directions on the specific roles of macrophage autophagy in tendon–bone junction repair.
Tumours contain many fibroblasts, endothelial cells, and leukocytes that are emerging as therapeutic targets complementary to targeting genetically unstable cancer cells. Immunotherapies directed towards this tumour microenvironment (TME) are increasingly effective. Targeting the endothelium has shown success, particularly in hepatocellular carcinoma (HCC). Cancer-associated fibroblasts (CAFs) are also attracting novel nascent therapeutic approaches, and fibroblast activation protein (FAP), which is specific to activated mesenchyme, is prominent amongst CAF markers. This review places emphasis upon FAP, human HCC, and FAP-targeting approaches for therapeutic benefit, including FAP inhibitors, radioligand therapy, T cell and antibody-dependent cytotoxicity/immunotherapy, and FAP-activated prodrugs.
Collagen, the primary structural protein of the extracellular matrix, shows marked structure–function duality in the tumor immune microenvironment (TIME). Biomechanical and biophysical alterations—matrix stiffening, viscoelastic energy dissipation, fiber alignment and tumor-associated collagen signatures, reduced pore size, and solid stress—create migration tracks, sequester signaling cues that regulate proliferation and metabolism, and from dense barriers that impede immune infiltration. These changes are sensed and transduced via mechanosensing and mechanotransduction pathways, thereby reinforcing malignant behavior and immune exclusion. Given its dynamic, spatiotemporally regulated roles, collagen is a promising therapeutic target to overcome immunotherapy resistance. This review examines the structural features, biological functions, and regulatory pathways of collagen within the TIME. Based on these insights, several clinical strategies were highlighted: targeting cancerassociated fibroblasts and profibrotic signaling to reduce fibrosis; remodeling the matrix enzymatically or physically; and inhibiting collagen receptor signaling. These approaches are often combined with immune checkpoint inhibition. Future directions will emphasize biomarker-guided stratification of collagen status; combining therapies informed by mechanobiology; and using scalable, noninvasive monitoring to optimize immunotherapy outcomes.
Intracranial hemorrhage (ICH) poses a serious risk to human health. The shift between pro-inflammatory (M1) and anti-inflammatory (M2) microglial phenotypes is a complex dynamic process. Quiescin sulfhydryl oxidase 1 (QSOX-1) plays a role in protecting cells from damage caused by oxidative stress and in cellular remodeling processes. This study explored how neuron-derived QSOX-1 protein influences the shift in microglial polarization between the M1 and M2 states, and its subsequent impact on nerve function after ICH.
QSOX-1 expression in the ICH mouse model was detected. Neuroinflammation, nerve damage, microglial phenotype, nerve function changes, and related signaling pathways were observed in mouse or cell models treated with QSOX-1.
After ICH, mass spectrometry analysis identified 353 differential proteins, of which the key role of QSOX-1 was verified by bioinformatics analysis. QSOX-1 in the ICH model was highly expressed in the neurons. After treatment with recombinant QSOX-1, the ICH model exhibited reduced neuroinflammation and nerve damage, improved nerve function, and a shift in microglia towards predominantly anti-inflammatory (M2) phenotypes. In vitro, QSOX-1 intervention led to reduced inflammation and neuronal cell death. When QSOX-1 expression was upregulated in microglia, the cells primarily shifted towards the M2 phenotype. This shift was accompanied by reduced levels of phosphorylated nuclear factor kappa B (NF-kB) and thioredoxin (TRX)-interacting protein (TXNIP)/NLR family pyrin domain containing 3 (NLRP3) protein, along with increased levels of phosphorylated inhibitor of NF-kB alpha (IkB-α) and TRX.
Neuron-derived QSOX-1 protein reduces neuroinflammation and promotes nerve function recovery after ICH by regulating microglia phenotype changes, which may be related to the IkB-α/NF-kB and TRX/TXNIP/NLRP3 axis.
Melatonin, a highly conserved indoleamine produced by the pineal gland and also in the mitochondria of many, perhaps all, extrapineal tissues, has emerged as a powerful antioxidant molecule. This review explores its role in counteracting lipid peroxidation (LP), a process that damages cellular membranes through the oxidative degradation of lipids. LP is involved in numerous pathological conditions, including neurodegenerative diseases, cancer, cardiovascular disorders, and aging. The article discusses how melatonin prevents, mitigates, or even reverses LP-induced cellular damage by acting as both a direct free radical scavenger and as an indirect regulator of antioxidant enzymes. A key point is melatonin’s amphiphilic nature, which enables it to access both lipid and aqueous cellular compartments, allowing for broad protection and supporting its diverse antioxidant, cytoprotective, and regulatory functions within the cell. Melatonin and its metabolites, such as N1-acetyl-N2-formyl-5-methoxykynuramine and N1-acetyl-5-methoxykynuramine, interact with reactive oxygen and nitrogen species (ROS and RNS), effectively reducing the LP chain reaction. This series of protective actions is known as the melatonin antioxidant cascade. This highlights that melatonin not only inhibits the initiation and propagation phases of LP but may also contribute to the repair of oxidized membrane components. We further summarize the experimental and clinical evidence supporting melatonin’s therapeutic potential in conditions in which LP plays a central role. Its ability to cross the blood–brain barrier and its synthesis in multiple tissues, combined with its low toxicity and minimal side effects, make it a promising therapeutic candidate. Additionally, melatonin modulates mitochondrial function and membrane fluidity, offering additional protection against oxidative stress. This positions melatonin not just as a passive antioxidant, but as an active therapeutic agent against oxidative damage. We advocate for deeper exploration of melatonin-based therapies in LP-driven diseases, proposing it as a multifunctional molecule with significant clinical value.
Lung cancer remains the leading cause of cancer-related mortality worldwide, with five-year survival rates below 20%, underscoring the importance of understanding key biological processes like autophagy in this disease. Autophagy, a lysosome-mediated degradation and recycling pathway, exerts context-dependent effects in lung cancer, functioning as both a tumor suppressor and a facilitator of tumor progression. On one hand, basal autophagy maintains cellular homeostasis and genomic integrity, thereby curbing malignant transformation. On the other hand, established lung cancer cells exploit autophagy to survive under metabolic stress, hypoxia, and therapeutic pressure (for example, during chemotherapy or targeted therapy), facilitating tumor growth, metastasis, and therapy resistance. This review synthesizes current insights into the molecular mechanisms of autophagy in lung cancer, detailing how core regulatory pathways—including the phosphoinositide 3 kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling axis, the liver kinase B1-AMP-activated protein kinase (LKB1–AMPK) energy-sensing pathway, and key autophagy-related genes such as Beclin 1 and autophagy related gene (ATG) proteins—intertwine with oncogenic signaling networks and cell death regulators (e.g., p53, Bcl-2). It also highlights the metabolic dimension of autophagy, illustrating how nutrient recycling and maintenance of mitochondrial function via autophagy enhance the metabolic plasticity and survival of lung tumors under stress. In addition, we critically appraise clinical attempts to modulate autophagy (e.g., with chloroquine/hydroxychloroquine (CQ/HCQ) or mTOR inhibitors), outlining reasons for mixed outcomes and proposing practical solutions for future trials. Finally, potential targeted therapeutic strategies are discussed, including approaches to inhibit cytoprotective autophagy and strategies to induce autophagy-dependent cell death using novel small-molecule activators. Collectively, the evidence supports a model in which precise, context-aware modulation of autophagy—guided by pharmacodynamic (PD) biomarkers and molecular stratification—will be key to improving outcomes in lung cancer.
TP53 gene mutations are common in breast cancer and are linked to chemoresistance. p63, a p53 family member, can induce apoptosis independently of p53, representing a potential therapeutic target in TP53-mutant tumors. This study evaluated the synergistic effects of SB431542, a TGF-β type I receptor inhibitor, and doxorubicin in TP53-mutant breast cancer cells.
Isoform-specific RT-PCR was used to assess TAp63 and ΔNp63 expression following SB431542 treatment in T47D, MDA-MB-231, and MDA-MB-468 cells. Cell viability was assessed using the CCK8 assay. Synergistic interaction was quantified using the Coefficient of Drug Interaction (CDI). Caspase-3/7 activity assays and immunocytochemistry analyses were performed to evaluate apoptotic signaling and p63 expression. Inhibition studies using PETα, a p53-family inhibitor, and a pan-caspase inhibitor were conducted to determine the pathway dependency of the observed effects.
SB431542 selectively increased TAp63 but not ΔNp63 expression in all three TP53-mutant breast cancer cells. GAS6, a TAp63 target, was also upregulated by SB431542. Treatment with SB431542 and doxorubicin used in combination significantly reduced cell viability (CDI 0.54–0.63), increased caspase activity, and enhanced p63 expression. The anticancer effect was significantly reduced by co-treatment with either the p53-family inhibitor or the pan-caspase inhibitor, confirming that the cytotoxic response was mediated through TAp63 and caspase activation.
SB431542 potentiates doxorubicin-induced apoptosis in TP53-mutant breast cancer cells by upregulating TAp63 and activating caspase-dependent pathways. These findings suggest that targeting the TGF-β/TAp63 signaling axis may offer a novel therapeutic approach to overcome chemoresistance in aggressive, TP53-mutant breast cancers.
Vascular dementia (VaD) is a prevalent cognitive disorder associated with cerebrovascular pathologies, in which hippocampal dysfunction plays a critical role. Impaired zinc homeostasis, mediated by the zinc transporters 3 (ZnT3) and transmembrane protein 163 (TMEM163), has been implicated in neuronal damage. However, the underlying mechanisms remain unclear. The purpose of this study is to elucidate the molecular mechanisms by which these zinc transporters may contribute to VaD pathogenesis, and to determine whether these mechanisms are involved in the development of VaD.
Rat primary hippocampal neurons were subjected to oxygen-glucose deprivation (OGD) to simulate ischemic conditions. To investigate the roles of ZnT3 and TMEM163, we employed siRNA-mediated silencing and plasmid-based overexpression. Neuronal viability was assessed using the methyl thiazolyl tetrazolium (MTT) assay, while apoptosis was quantified via TdT-mediated dUTP nick-end labeling (TUNEL) staining. Intracellular and extracellular zinc levels were measured using FluoZin-3 fluorescence and ELISA, respectively. Protein and mRNA expression levels were analyzed by western blot and real-time quantitative polymerase chain reaction (RT-qPCR). Protein-protein interactions were examined through co-immunoprecipitation, and subcellular localization was determined via cell surface biotinylation.
OGD induced significant extracellular zinc overload, neuronal apoptosis, and reduced cell viability, concomitant with upregulated expression of ZnT3 and TMEM163 (all p < 0.001). Overexpression of these transporters exacerbated zinc efflux and neuronal damage under OGD, whereas their silencing attenuated zinc overload and neuronal degeneration (p < 0.001). Co-immunoprecipitation confirmed a physical interaction between ZnT3 and TMEM163. Furthermore, OGD triggered the translocation of both proteins from the cell membrane to the cytoplasm (p < 0.001), suggesting ischemia-induced dysregulation of zinc transport dynamics. These findings demonstrate that ZnT3 and TMEM163 cooperatively modulate zinc homeostasis and that their dysregulation during OGD contributes to neuronal injury.
ZnT3 and TMEM163 are critical regulators of zinc homeostasis in hippocampal neurons. Their dysregulation under ischemic conditions promotes extracellular zinc overload and exacerbates neuronal damage, highlighting their potential therapeutic relevance in VaD.
Matrix metalloproteinases (MMPs) are enzymes that degrade extracellular matrix (ECM) proteins and activate cytokines and chemokines, playing a critical role in tissue remodeling. Monitoring MMP activity is important for diagnosing and tracking diseases, studying disease progression, and developing new diagnostic and therapeutic strategies. This article highlights methods for detecting active gelatinases, specifically MMPs-2, -7, -9, and -13 in various biological samples.
The described protocol utilizes an electrophoresis-based biochemical technique commonly used for protein analysis, with the key modification of incorporating a specific substrate, such as gelatin or casein, into the gel. This method, known as zymography, is named according to the substrate used. For example, it is called ‘gelatin zymography’ when gelatin is used as the substrate.
When performing zymography, it is crucial to account for the amount of proteinase in different samples, such as plasma which contains significantly higher concentrations of active MMPs compared to other body fluids, tissues, or cells. As a result, only small volumes of plasma are required to produce distinct bands in the zymography gel. Additionally, our findings show that MMP activity, especially active MMP-9, is significantly higher in sonicated samples compared to non-sonicated samples. Therefore, careful consideration of sample preparation, processing, and the amount of protein loading is necessary to achieve high-quality zymography results.
The optimized zymographic protocol presented here enables reliable detection of endopeptidase activities using gelatin or casein as substrates. Other substrates, such as collagen and fibronectin, can also be used to detect collagenase and fibronectinase activities, respectively. This approach facilitates a deeper understanding of metalloproteinase roles in ECM synthesis and degradation, particularly in matrix-related pathologies, including cancer and other tissue disorders. Zymography remains a widely used technique for visualizing ECM protein-degrading enzyme activity in plasma, urine, other body fluids, tissues, and cell culture samples.
Vitamin D is essential for skeletal health, but its role in redox homeostasis and cellular senescence during aging in vivo is unclear. We therefore investigated whether active vitamin D insufficiency accelerates bone loss via oxidative stress and senescence pathways.
Male wild-type (WT) and Cyp27b1 haploinsufficient mice (modeling vitamin D insufficiency) were treated with N-acetylcysteine (NAC) or 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. Double-mutant p16-/-Cyp27b1+/- mice were used to assess the role of the tumor suppressor protein p16. Mice were maintained until 8 months of age in a specific pathogen-free facility. Outcomes included lifespan (n = variable per group, monitored daily); generation of oxidative stress (determined by serum malondialdehyde [MDA] levels via assay kit); generation of bone reactive oxygen species [ROS] (determined via flow cytometry), development of DNA damage (indicated by 8-hydroxy-2′-deoxyguanosine [8-OHdG] and γ-H2A.X generation and determined via immunohistochemistry and Western blot); and senescence (assessed by generation of β-galactosidase [β-gal], p16, and senescence-associated secretory phenotype [SASP] cytokines as determined via staining, blot, and real-time reverse transcription polymerase chain reaction). Additionally, bone microarchitecture was examined via micro-computed tomography and histomorphometry. Data from at least 5 mice per group were analyzed using unpaired Student’s t-test for two-group comparisons and two-way analysis of variance for multi-group comparisons, with significance at p < 0.05.
Compared with wild-type controls, Cyp27b1+/- mice showed a significantly shorter lifespan, higher oxidative stress, greater DNA damage, increased senescence markers, and lower trabecular bone volume (all p < 0.05). In Cyp27b1+/- mice, treatment with either N-acetylcysteine or 1,25(OH)2D3 significantly improved survival, reduced oxidative stress and DNA damage, attenuated senescence markers, and increased bone volume relative to untreated Cyp27b1+/- mice (p < 0.05 for all relevant comparisons; n = 5 per group). Genetic deletion of p16 in Cyp27b1+/-mice similarly increased bone volume and reduced senescence-associated readouts compared with Cyp27b1+/- controls (p < 0.05; n = 5).
Active vitamin D insufficiency accelerates skeletal aging in vivo through a pathway involving reactive oxygen species-DNA damage-p16/senescence-associated secretory phenotype. Antioxidants, vitamin D repletion, or p16 inhibition rescued bone loss, highlighting redox-senescence axes as potential therapeutic targets for osteoporosis.
Psoriasis is a chronic inflammatory skin disease driven by an abnormal immune response. Mesenchymal stem cells have strong immunomodulatory properties. Therefore, we investigated the therapeutic effects and underlying mechanisms of human adipose-derived mesenchymal stem cells (hAD-MSCs) in a psoriasis-like mouse model.
A psoriasis-like mouse model was established and hAD-MSCs were administered via subcutaneous injection. Skin thickness was evaluated using hematoxylin and eosin (H&E) staining, and disease severity was assessed using the Psoriasis Area Severity Index (PASI). Neutrophil counts and Signal Transducer and Activator of Transcription 3 (STAT3) positive keratinocytes in the skin were evaluated by immunohistochemistry (IHC). Additionally, we evaluated the cytokine expression by quantitative PCR (q-PCR).
hAD-MSCs significantly attenuated psoriasis-like skin inflammation. Neutrophil infiltration was markedly reduced in psoriatic lesions following hAD-MSC treatment. We found that hAD-MSCs inhibit neutrophil recruitment by lowering CXCL1 levels in the skin, which may be linked to reduced phosphorylation of STAT3.
Our findings highlight the potential of hAD-MSCs as a potent therapeutic strategy for inhibiting neutrophil recruitment and ameliorating psoriasis-like inflammation.
Pancreatic neoplasms, particularly pancreatic adenocarcinoma (PAAD), are aggressive malignancies marked by extensive infiltration of cancer-associated fibroblasts (CAFs) and a highly complex tumor immune microenvironment. These pathological features are strongly associated with poor patient survival. However, the precise mechanisms underlying the role of CAFs in PAAD have not been determined.
To systematically analyze the functions of CAFs in PAAD and their associations patient outcomes, an integrative approach combining multi-omics data with experimental validation was used.
Integrated weighted gene co-expression network and protein–protein interaction network analyses revealed CAF-related genes with functional significance. Experimental verification was performed to examine the influence of candidate CAF-related genes identified using multi-database analyses on tumor cell behavior. COL28A1, TGFB2, TGFBI, PLOD2, and COL22A1 were core genes closely associated with CAFs. Patients in the high-risk group demonstrated a higher immune escape ability and lower predictive response rate to immunotherapy than those in the low-risk group. Several potential targeted therapeutic compounds were identified, including dihydrorotenone and sorafenib. Single-cell RNA sequencing and expression analyses confirmed elevated expression of TGFBI and PLOD2 in CAFs. Functional experiments demonstrated that PLOD2 promotes tumor progression by regulating extracellular matrix remodeling.
This study provides insights into the molecular mechanisms underlying PAAD and establishes a theoretical foundation for the development of CAF-targeting therapeutic strategies.
Phosphodiesterases (PDEs) are a huge superfamily of enzymes that fine-tune the intracellular levels of cyclic nucleotides —cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP)—thus playing a pivotal role in the control of many cellular processes. While traditionally studied in the context of cardiovascular and neurological systems, mounting evidences highlight a crucial involvement of PDEs in metabolic homeostasis. This review explores the expanding landscape of PDEs function beyond classical cyclic nucleotide degradation, focusing on their roles in glucose and lipid metabolism and their implications in metabolic disorders, including obesity, type 2 diabetes (T2DM), and metabolic syndrome (MetS). Starting from an overview of the PDE superfamily, this work deeply examines the compartmentalized actions of cAMP-dependent protein kinase A (PKA) and cGMP-dependent protein kinase G (PKG) signaling pathways in key metabolically active tissues integrating PDE activities across different organs and disease states to offer a holistic view of their metabolic relevance. Special attention is given to the therapeutic relevance of PDE inhibitors (PDEi), distinguishing between established applications and emerging strategies targeting specific PDE isoforms in metabolic disease contexts to underscore the evolving concept that PDEs act as dynamic regulators of metabolic signaling networks. Understanding their isoform-specific and tissue-specific actions could thus open new avenues for therapeutic intervention in complex metabolic disorders.
High-risk neuroblastoma (NB) remains a therapeutic challenge with a poor prognosis, necessitating the identification of novel prognostic biomarkers and effective therapeutics.
We analyzed transcriptomic datasets from public repositories using weighted gene co-expression network analysis to identify gene modules associated with prognosis. Consensus clustering stratified patients into distinct subgroups. Differential expression analysis, integrated with 80 machine learning algorithm combinations, prioritized hub genes to construct a risk-scoring model, which was implemented via an online platform. We then screened the new drug eugenol using the proximity algorithm and explored its feasibility through in vitro trials.
Consensus clustering based on prognosis-associated modules revealed two patient subgroups with significantly different survival differences (p < 0.001). A set of six hub genes (chromosome 21 open reading frame 58 (C21orf58), cannabinoid receptor 1 (CNR1), laminin alpha 4 (LAMA4), leptin receptor (LEPR), solute carrier family 25 member 10 (SLC25A10), and telomerase reverse transcriptase (TERT)) was identified and used to build a risk-scoring model, accessible at online platform. Leveraging this model, we identified eugenol as a potential therapeutic candidate. Transcriptome analysis showed that eugenol selectively targeted high-risk NB cell populations predicted by the model. Preliminary in vitro experiments investigating its mechanism of action indicated that eugenol primarily functions by inhibiting the MYC-cyclin D1 (CCND1) axis.
This study establishes an integrated precision medicine framework for NB, identifying a new high-risk group and suggesting eugenol as a promising therapeutic candidate for this group, potentially acting through MYC-CCND1 axis suppression.
Transcription of the hepatitis B virus (HBV) is regulated by the acetylation status of H3/H4 histones bound to the covalently closed circular DNA (cccDNA) minichromosome. Thus, this study aimed to investigate whether sirtuin 7 (SIRT7), an NAD⁺-dependent acetylated lysine 18 of histone H3 (H3K18Ac) deacetylase, represses HBV transcription by catalyzing H3K18 deacetylation on the cccDNA minichromosome.
We investigated the effects of SIRT7 overexpression/knockdown on HBV transcription and histone acetylation in HepG2.2.15 cells, which constitutively express HBV, and HBV-infected HepG2-NTCP cells. Viral RNA levels and hepatitis B surface and e antigen levels were quantified using reverse transcription quantitative polymerase chain reaction and enzyme-linked immunosorbent assays, respectively. Meanwhile, Western blotting was used to determine protein expression levels. The association between DNA damage-binding protein 1 (DDB1) and cccDNA and the acetylation status of cccDNA minichromosome-associated H3K18 were analyzed using chromatin immunoprecipitation. Co-immunoprecipitation was used to detect protein–protein interactions. Data were statistically analyzed using Student’s t-test.
This study demonstrated that SIRT7 enhanced rather than repressed HBV transcription. Mechanistically, SIRT7 promoted HBV transcription by upregulating DDB1, a protein essential for HBV transcription, and by facilitating the recruitment of DDB1 to the cccDNA minichromosome. SIRT7 knockdown inhibited DDB1 expression and reduced DDB1 enrichment on the cccDNA, thereby suppressing HBV transcription. Conversely, SIRT7 overexpression upregulated DDB1 expression and enhanced DDB1–cccDNA binding, eventually promoting HBV transcription.
SIRT7 enhances HBV transcription by upregulating DDB1 expression and promoting an association between DDB1 and cccDNA.
Ulcerative colitis (UC) is a chronic inflammatory disorder primarily affecting the rectum and colon. This study aimed to identify potential therapeutic targets that may inhibit UC progression and mitigate patient suffering.
UC-related datasets were retrieved from the Gene Expression Omnibus database. Differential expression analysis, weighted gene co-expression network analysis, immunoinfiltration analysis, and pyroptosis scoring were employed to identify key pyroptosis-related genes implicated in UC pathogenesis. A dextran sulfate sodium salt (DSS)-induced mouse model of UC was established, and neutrophil extracellular traps (NETs) were induced in neutrophils by stimulation with phorbol 12-myristate 13-acetate (PMA). Histopathological changes in mouse colon tissues were assessed by hematoxylin-eosin staining, and NET formation was evaluated via immunofluorescence. The expression of aquaporin 9 (AQP9), peptidylarginine deiminase 4 (PAD4), zonula occludens 1 (ZO-1), occludin, and proteins related to pyroptosis and the JAK2-STAT3 pathway was determined by Western blotting. Levels of inflammatory cytokines were measured by enzyme-linked immunosorbent assay (ELISA), production of reactive oxygen species was assessed using fluorescent probes, and intestinal epithelial cell viability and death were evaluated using the cell counting kit-8 (CCK-8) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays, respectively.
Five hub genes (AQP9, S100A8, S100A9, S100A12, and VNN2) were identified through bioinformatics analysis, with AQP9 selected for further investigation. Single-cell analysis and immunofluorescence revealed that AQP9 was predominantly expressed in neutrophils and upregulated in the colon tissues of mice with UC and PMA-stimulated neutrophils. Knockdown of AQP9 in PMA-treated neutrophils led to suppression of the JAK2-STAT3 pathway, reduced pyroptosis, and decreased NET formation. Upon co-culture with intestinal epithelial cells, AQP9 knockdown resulted in enhanced epithelial cell viability, reduced apoptosis, and upregulation of ZO-1 and occludin. Conversely, treatment of neutrophils from the PMA+si-AQP9 with a JAK2-STAT3 pathway agonist increased pyroptosis, enhanced the formation of NETs, and induced epithelial cell injury. Similarly, treatment with a pyroptosis agonist enhanced both pyroptosis and the formation of NETs, further aggravating epithelial damage.
Knockdown of AQP9 inhibits JAK2-STAT3 pathway-mediated pyroptosis, thereby reducing the formation of NETs and attenuating intestinal epithelial cell injury.
Glioma, the most common brain tumor in adults, exhibits marked hypoxia and invasiveness. Endoplasmic reticulum stress (ERS) and the unfolded protein response (UPR) have been implicated in tumor progression, while epithelial mesenchymal transition (EMT) drives invasion and metastasis.
This study explored the role of ERS, particularly the PKR-like endoplasmic reticulum kinase (PERK) pathway, in promoting EMT and malignancy in glioma. Based on publicly available bulk transcriptomic data, we analyzed PERK activity in high-grade and hypoxic gliomas. PERK activation across glioma subtypes was compared using publicly available single-cell sequencing, and its correlation with EMT upregulation was evaluated using pseudotime analysis. The effects of PERK on glioma migration and invasion in a hypoxic environment were investigated using PERK-silenced glioma cell lines. In vivo tumorigenicity was assessed in nude mice by measuring tumor size and EMT marker expression. Intercellular communication was examined using CellChat analysis. Hypoxic niche regions were identified using publicly available spatial transcriptomics with PERK-EMT co-localization.
Hypoxia-induced PERK activation promoted EMT, enhancing glioma cell migration and tumor growth. High PERK signatures correlated with EMT activation in aggressive gliomas. Genetic silencing of PERK reduced the expression of EMT-related proteins, an effect partially reversed by hypoxia. Inhibition of PERK signaling decreased tumor size in mice. PERK-activated glioma subpopulations exhibited stronger cell–cell communication through secreted phosphoprotein 1 (SPP1)-CD44 interactions. Spatial transcriptomic analysis confirmed enrichment of the PERK/EMT pathway in hypoxic niches alongside SPP1-CD44 co-localization.
These findings reveal PERK-driven EMT as a key mechanism linking ER stress to glioma progression, with hypoxia reinforcing this axis. Targeting the PERK signaling axis or SPP1-CD44 interactions may offer novel therapeutic strategies against aggressive gliomas.
Ischemic stroke leads to significant neuronal damage, and impaired angiogenesis remains a critical factor limiting post-stroke recovery. Ginkgolide B (GB), a key component of Ginkgo biloba extract, has shown potential neuroprotective effects, but its pro-angiogenic mechanisms remain unclear.
To investigate the effects of GB, we established an oxygen–glucose deprivation/reperfusion (OGD/R) model using bEnd.3 cells. Potential molecular targets of GB were explored through a combination of network pharmacology analysis, protein–protein interaction (PPI) network construction, pathway enrichment, and molecular dynamics simulations. Based on these predictions, a series of in vitro assays—including Cell Counting Kit-8 (CCK-8), 5-ethynyl-2′-deoxyuridine (EdU) incorporation, wound-healing, Transwell migration, and Matrigel tube formation tests—were performed to evaluate cell viability, proliferation, migration, and angiogenic activity. Western blotting was conducted to detect AKT serine/threonine kinase 1 (AKT1), vascular endothelial growth factor (VEGF), and Angiogenin (Ang) expression and clarify the role of the AKT1/VEGF/Ang pathway.
Bioinformatics analysis identified 19 potential targets, among which AKT1, Matrix Metalloproteinase 9 (MMP9), and Prostaglandin-Endoperoxide Synthase 2 (PTGS2) exhibited the highest relevance. GB showed no evident cytotoxicity at concentrations up to 40 μM and mitigated the OGD/R-induced reduction in cell viability. At this concentration range, GB also enhanced endothelial proliferation, migration, and tube formation in bEnd.3 cells. Mechanistic studies revealed that MK2206 inhibition of AKT1 markedly suppressed AKT1 expression (p < 0.01), impaired angiogenic capacity, and aggravated ischemic–hypoxic injury, whereas GB treatment significantly increased VEGF and Ang expression (p < 0.01), likely via AKT1 upregulation (p < 0.01).
GB promotes angiogenesis and exerts neuroprotective effects by activating the AKT1/VEGF/Ang signaling pathway, suggesting its potential therapeutic value for ischemic stroke–related injuries.
Knee osteoarthritis (KOA), a chronic degenerative joint disease, is primarily driven by inflammation-induced cartilage degradation, which represents its core pathological feature. Eupatorin, with its distinct anti-inflammatory properties, has emerged as a promising candidate for KOA research. This study aimed to explore the therapeutic potential of Eupatorin and elucidate its underlying mechanisms in KOA through an integration of network pharmacology analysis and experimental validation.
Potential targets of Eupatorin and KOA-related genes were retrieved from multiple databases, and the overlapping targets were utilized to build a protein‒protein interaction (PPI) network to identify core targets. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to characterize the associated biological processes (BP), molecular functions (MF), and cellular components (CC). Additionally, molecular docking was performed to assess the binding affinities of Eupatorin with the core targets. Direct target engagement was confirmed using a cellular thermal shift assay (CETSA). Finally, biological experiments using interleukin-1β (IL-1β)-stimulated primary rat chondrocytes were carried out to validate the protective effects of Eupatorin through its anti-inflammatory activity.
Network pharmacology analysis revealed 46 overlapping targets, with Matrix Metallopeptidase 9 (MMP9), Epidermal Growth Factor Receptor (EGFR), and Prostaglandin G/H synthase 2 (PTGS2) as key nodes within the PPI network. GO and KEGG enrichment analyses revealed significant associations with inflammatory responses and extracellular matrix (ECM) metabolism, particularly the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) and estrogen signalling pathways. Molecular docking further confirmed strong binding affinities between Eupatorin and key targets, including MMP9, EGFR, and PTGS2. CETSA validated the direct binding of Eupatorin to PTGS2. Eupatorin significantly inhibited IL-1β-induced cytokine expression and ECM degradation while promoting ECM synthesis and restoring impaired autophagy in inflamed chondrocytes, as indicated; however, no significant effect on cellular senescence was observed. Mechanistically, Eupatorin exerted its protective effects on chondrocytes by attenuating the upregulation of the PI3K/AKT and estrogen signalling pathways.
Eupatorin has demonstrated potential for use in KOA therapy by targeting inflammation and ECM, and by regulating the PI3K/AKT and estrogen-associated signaling pathways.
Gliomas are the most aggressive primary malignancies of the central nervous system (CNS) and exhibit marked heterogeneity that is closely associated with metabolic reprogramming. Emerging evidence underscores the pivotal role of lactylation modifications in shaping the tumor microenvironment (TME) and facilitating glioma progression. This study aimed to systematically identify key lactylation-related genes (LRGs), elucidate their functional roles and associated pathways, and explore their potential as novel therapeutic targets using multi-omics data.
We combined various datasets from the TCGA, GEO, and CGGA databases, including RNA-seq, single-cell RNA sequencing (scRNA-seq), and spatial transcriptomics. Key LRGs were identified through a multi-step analytical pipeline that involved processing scRNA-seq data using (Seurat, scoring), cell-type-specific lactylation scoring (AUCell), high-dimensional weighted gene co-expression network analysis (hdWGCNA) and applying rigorous machine learning-based feature selection utilizing 10 algorithms and 101 combinatorial strategies. We comprehensively assessed the prognostic value associated with the immune microenvironment, and spatiotemporal heterogeneity of the prioritized RAN. Functional validation was executed using shRNA-mediated knockdown in glioma cell lines, including LN229, U87, and U251, while evaluating proliferation (CCK-8, colony formation, EdU), migration (wound healing), invasion (Transwell), and pathway activity (using western blot).
scRNA-seq analysis revealed distinct lactylation enrichment patterns across glioma cell types, with malignant cells exhibiting the highest scores. hdWGCNA identified a gene module (royal blue) strongly correlated with lactylation activity (correlation = 0.75). The intersection of this module with a curated set of LRGs yielded 22 candidate genes. Subsequent machine learning analysis using (ENet, α = 0.4) prioritized six core LRGs (PDAP1, ALYREF, CBX3, MAGOH, RAN, TMSB4X). RAN, an understudied gene in glioma, was selected for further investigation. High RAN expression correlated significantly with poor patient prognosis, reduced immune cell infiltration (assessed by ESTIMATE, CIBERSORT, xCell, ssGSEA), and distinct spatiotemporal heterogeneity within tumors (analyzed using spatial transcriptomics, Monocle2). Glioma cell invasion, migration, colony formation, and proliferation were all markedly inhibited by RAN knockdown. Mechanistically, reduced p-AKT levels following knockdown and functional rescue with a PI3K/AKT activator (SC79) indicate that RAN increased these malignant traits by activating the PI3K/AKT signaling pathway.
Our study established lactylation modifications as a crucial regulator of the TME and glioma progression. Through integrative multi-omics analysis and robust machine learning techniques, we determined that RAN was a novel lactylation-associated gene. RAN is a potent, independent prognostic biomarker that promotes glioma malignancy via the PI3K/AKT pathway. Our results demonstrate RAN as a prospective therapeutic target and establish a novel framework for individualized therapy for glioma.
Disruption of the blood labyrinth barrier (BLB) is considered a pathological cause of diverse hearing impairments. Perivascular-resident macrophage-like melanocytes (PVM/Ms) play a critical role in maintaining inner ear homeostasis and BLB integrity. Activation of PVM/Ms leads to decreased production of pigment epithelium-derived factor (PEDF), contributing to BLB breakdown. This study investigated the role of the adenosine A2A receptor (A2AR) pathway in lipopolysaccharide (LPS)-induced inflammation in PVM/Ms and elucidated the underlying mechanisms.
The anti-inflammatory effects of adenosine and its specific receptor A2AR were evaluated in LPS-induced PVM/Ms. The levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and tissue inhibitor of matrix metalloproteinase 1 (TIMP-1) were measured by quantitative real-time PCR (qRT-PCR) and enzyme linked immunosorbent assay (ELISA). Additionally, matrix metalloproteinase-9 (MMP-9) and PEDF were quantified using western blot and ELISA, respectively. An endothelial cell (EC)-PVM/M co-culture model exposed to LPS was established and treated with adenosine and SCH58261 to assess effects on BLB permeability.
LPS treatment significantly changed the production of inflammatory factors, including IL-6 and TNF-α, as well as MMP-9, TIMP-1, and PEDF. These changes were abrogated by adenosine, which also reduced the production of reactive oxygen species (ROS) and inhibited the activation of PVM/Ms. SCH58261 partially reversed the effects of adenosine following LPS treatment. The p38 MAPK pathway was found to be involved in adenosine regulation of LPS-induced PVM/Ms.
Adenosine attenuates the inflammatory activation of PVM/Ms and enhances their ability to maintain endothelial barrier integrity by binding to A2AR. The findings support adenosine and A2AR as potential therapeutic targets for treating hearing impairments.
Exosomes are specialized secreted vesicles for intercellular communication and signaling pathways as specialized secreted vesicles. Multiple studies have suggested the potential roles of hepatocyte-derived exosomes as biomarkers of liver injury and facilitators of hepatocyte proliferation and liver regeneration.
By utilizing murine models of hepatic ischemia-reperfusion injury (IRI), we examined the impact of hepatocyte-derived exosomes on mitigating hepatic IRI.
Our experiments have demonstrated that significantly lower levels of alanine transaminase, aspartate transaminase, and lactate dehydrogenase in mice treated with hepatocyte-derived exosomes compared with mice treated with phosphate-buffered saline (PBS). Furthermore, hepatocyte-derived exosomes inhibited hepatocyte apoptosis, reduced levels of inflammatory cytokines, and suppressed the entry of inflammatory cells into the liver following hepatic IRI. Complement 3d (C3d) expression showed a notable decrease in exosome-treated mice compared with PBS-treated mice, suggesting that hepatocyte-derived exosomes effectively inhibited complement activation during hepatic IRI. Blocking the fusion of exosomes with cells using Annexin V weakened the protective effects of the exosomes against hepatic IRI.
Our findings highlight the ability of hepatocyte-derived exosomes to mitigate hepatic IRI by inhibiting complement activation. These results reveal a novel role for exosomes in blocking complement activation, suggesting a potential new therapeutic avenue for preventing hepatic IRI.
The phycobilisomes (PBS) of cyanobacteria and red algae are unique light-harvesting protein-pigment complexes that utilize bilin derivatives for light absorption and energy transfer. These extramembranous mega-Dalton complexes are specifically organized and anchored to photosystem II (PSII) via the multi-domain core-membrane linker (LCM). While Arm2 is the longest segment in LCM domain, its specific functions remain uncharacterized.
A series of Synechocystis sp. PCC 6803 mutants with complete or partial deletions of Arm2 and its adjacent Rep domains within LCM were constructed. The assembled PBSs were isolatedand characterized using sucrose gradient ultracentrifugation, absorption and fluorescence spectroscopy, and SDS-PAGE. Physiological functions were further assessed by analyzing growth, photosynthetic performance, state transitions, and non-photochemical quenching (NPQ).
Our results reveal that the super-secondary element of helix-turn-helix of Arm2 is critical for assembling the two longitudinal halves of PBS. The truncation of either or both helices of Arm2 results in the specific degradation of the longitudinal half harboring the terminal emitter, ApcD. Consequently, these mutants were deficient in state transitions and exhibited accelerated recovery from orange carotenoid protein (OCP)-mediated NPQ. We also identified the Arm2(37–67) motif likely involved in attaching the rods to the core, whereas the Arm2(68–129) region had no significant impact on PBS assembly.
The helix-loop-helix element of Arm2 is essential for the longitudinal integrity of the PBS core and is a prerequisite for state transitions. These results suggest that state transitions may involve longitudinal rearrangements within the PBS structure, rather than lateral movements of the two halves, implicating that state transitions result from the longitudinal instead of the lateral moves of the two halves of the PBSs.
This integrated study aimed to characterize fibroblast heterogeneity in diabetic ulcers and evaluate the efficacy of platelet-rich plasma (PRP) using multi-omics approaches.
We analyzed single-cell RNA sequencing (scRNA-seq) data (GSE165816) from healed (n = 9) and non-healed (n = 5) patients with diabetic foot ulcers (DFU) to characterize fibroblast dynamics, utilizing cell–cell communication analysis, transcription factor profiling, and pseudotime trajectory reconstruction. A streptozotocin-induced diabetic ulcer rat model was established to validate the therapeutic effects of PRP.
scRNA-seq identified 13 cell types, with fibroblasts showing the most significant proportional increase in healed DFU (32% versus 25% in non-healed tissue). Fibroblast-centric communication networks revealed synergistic interactions with endothelial and keratinocyte lineages. Three key transcription factors (PLAGL1, RUNX2, and ZKSCAN7) were upregulated in healed fibroblasts, regulating pathways related to extracellular matrix (ECM) synthesis, angiogenesis, and cell migration. Pseudotemporal analysis confirmed the differentiation of fibroblasts toward ECM-producing states, with enrichment of platelet-derived growth factor (PDGF) signaling pathways. In the rat model, PRP treatment resulted in epidermal/dermal thickening, reduced inflammatory infiltration, and transcriptomic reprogramming that converged with non-diabetic profiles. Venn analysis identified a 26-core gene signature (e.g., COL1A1, FN1) associated with fibroblast-mediated ECM reorganization.
Fibroblasts drive diabetic ulcer healing via transcription factor-regulated functional networks. PRP accelerates tissue repair by modulating fibroblast ECM-related gene expression, with the 26-gene signature providing a promising foundation for novel diagnostic and therapeutic targets.
Mineral deposition in the extracellular matrix (ECM) is a highly organized process initiated by matrix vesicles (MVs) released from mineralization-competent cells, such as osteoblasts. In bone pathologies, osteogenic inducers (ions, hormones, nanoparticles) are becoming increasingly vital for the repair of damaged tissue. Among these inductors, strontium ranelate (SR), first suggested for treating osteoporotic patients, stands out. The bioactive strontium ion (Sr2+) has a dual mechanism of action in bone homeostasis: it activates osteoblasts, promoting bone formation, and inhibits osteoclasts, limiting bone resorption. Recent research has focused on how Sr2+ influences osteoblast function, but its effects on the mineralization process have not been explored. For this study, we hypothesized that Sr2+ modulates mineralization-competent cells at two levels: (a) it activates the extracellular signal-regulated kinase 1/2 (Erk1/2) and cAMP response element-binding protein (CREB) osteogenic signaling pathways, increasing mineral towards in the ECM, and (b) it regulates MV release and function. Advanced lipidomic analysis examined how Sr2+ affects the MV lipid profile, which is pivotal for MV biogenesis and bone formation.
We performed an MTT assay to assess the cytotoxicity of CaCl2 and SR. Alizarin Red and Von Kossa staining were used to track mineral deposition towards the ECM. We assessed the phosphorylation states of ERK and CREB by western blotting and the osteogenic-related gene levels by quantitative real-time PCR. Biophysical characterization of 17A11-derived MVs was performed by nanoparticle tracking analysis (NTA), dynamic light scattering (DLS), and zeta potential. Mineral deposition and characterization were performed by turbidimetry and Fourier transform infrared spectroscopy (FTIR), respectively. MV activity was studied by alkaline phosphatase activity. We also performed a Western blot analysis to assess MV markers. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) were applied to investigate changes in membrane fluidity and the vesicles’ conformation. We explored the changes in lipid profiles using state-of-the-art lipidomic analysis.
Our findings demonstrate that Sr2+ activates the Erk1/2 and CREB pathways, leading to a dose-dependent increase in ECM mineralization. Additionally, the viscoelastic properties of MVs from Sr2+-stimulated 17IIA11 cells, a preodontoblast progenitor cell line, were altered, as demonstrated by AFM and TEM, which we linked to modifications in their lipid composition, as revealed by the enrichment of ceramide (Cer) and sphingomyelin (SM), both of which play pivotal roles in bone development.
Our study demonstrated that Sr2+ affects the initiation of the mineralization process by changing the release and lipid composition of MVs, and acts, in part, through Erk1/2 and CREB signaling pathways.
Epinephrine (Epi, adrenaline) is routinely used during cardiopulmonary resuscitation (CPR) for cardiac arrest and is a first line treatment according to the international advanced life support (ALS) guidelines, which recommend 1 mg Epi be administered every 3–5 minutes during CPR. However, specific pharmacological factors that may distinguish Epi from other vasopressor agents used during CPR are unclear. This opinion article argues that one such factor, perhaps even the most important, is the activation of the β2-adrenergic receptor (AR) subtype, which only Epi, among all vasopressor hormones, can induce. β2AR activation equips Epi with more robust capabilities for pulse generation in the pacemaker cells (sinoatrial node) for the heart and of restoring contractile function in ischemic/hypoxic cardiomyocytes via sodium/potassium pump activation, compared to all other vasopressor hormones, including the closely related catecholamine norepinephrine (NE, noradrenaline). These additional actions of Epi via the β2AR, which are probably not shared by NE or other vasopressor agents, may make it particularly useful in situations where simple blood pressure elevation is insufficient, such as cardiac arrest.