Grobs Y, Lemay SE, Mougin M
… +12 more, Theberge C, Boucher M, Breuils-Bonnet S, Martineau S, Bourgeois A, Pelletier A, Fillon M, Perron J, Potus F, Provencher S, Boucherat O, Bonnet S
BACKGROUND: Post-surgical restenosis in patients with coronary artery disease (CAD) is a pathological vascular remodeling process characterized by neointimal hyperplasia, which is mainly driven by phenotypic switching of...BACKGROUND: Post-surgical restenosis in patients with coronary artery disease (CAD) is a pathological vascular remodeling process characterized by neointimal hyperplasia, which is mainly driven by phenotypic switching of vascular smooth muscle cells toward a synthetic and proliferative state. This study investigated a novel signaling pathway to promote the proproliferative phenotype of vascular smooth muscle cells and contribute to the neointimal hyperplasia development. METHODS: Using comparative proteomic analysis and Western blotting, expression of hypusine signaling components was evaluated in human primary cultures of coronary artery smooth muscle cells isolated from controls and patients with CAD, as well as in 3 preclinical animal models of restenosis: rat carotid injury, mouse carotid ligation, and canine coronary artery bypass graft. CAD-coronary artery smooth muscle cell proliferation was assessed by Western blot and immunofluorescence with pharmacological (N1-guanyl-1,7-diaminoheptane) and molecular (shRNA) inhibitors of DHPS (deoxyhypusine synthase). The contribution of hypusine signaling to neointimal hyperplasia was investigated using both pharmacological and genetic approaches. In addition, human saphenous vein and human coronary artery tissue cultures were used to explore the translational potential of targeting hypusine signaling to prevent neointimal hyperplasia. RESULTS: All components of the hypusine pathway (eIF5A (eukaryotic translation initiation factor 5A), DOHH (deoxyhypusine hydroxylase), and DHPS were significantly overexpressed in CAD-coronary artery smooth muscle cells and in preclinical animal models of restenosis. Pharmacological and molecular inhibition of DHPS reduced eIF5A hypusination, vascular smooth muscle cell proliferation, and expression of ECM (extracellular matrix) proteins. Proteomic and KEGG analyses demonstrated disruption of cell-cycle and DNA replication pathways, including a downregulation of TTK (threonine tyrosine kinase). Our findings suggest that TTK acts as a downstream effector of hypusine signaling, which partly mediates the proliferative effects observed in CAD-coronary artery smooth muscle cells. In vivo, pharmacological and smooth muscle cell-targeted inactivation of DHPS significantly reduced neointimal hyperplasia without adverse effects. Finally, ex vivo human tissue culture confirmed that N1-guanyl-1,7-diaminoheptane mitigates growth factor-induced vascular remodeling. CONCLUSIONS: Hypusine signaling is a critical regulator of vascular smooth muscle cell proliferation for neointimal hyperplasia. Inhibiting DHPS reduces vascular remodeling, making it a promising target for preventing restenosis after coronary interventions.
BACKGROUND: Monocyte-derived macrophages play a significant role in the initiation and progression of atherosclerosis by transforming into lipid-laden foam cells and regulating vascular inflammation. However, the molecul...BACKGROUND: Monocyte-derived macrophages play a significant role in the initiation and progression of atherosclerosis by transforming into lipid-laden foam cells and regulating vascular inflammation. However, the molecular mechanisms that regulate macrophage lipid accumulation, phenotype, efferocytic capacity, and atherosclerosis are incompletely understood. Our preliminary studies revealed increased expression of LGR4 (leucine-rich repeat-containing G protein-coupled receptor 4) in human atherosclerotic arteries. Additional experiments demonstrated increased LGR4 levels in atherogenic oxidized low-density lipoprotein-treated macrophages. However, the macrophage-specific role of LGR4 in atherogenesis has never been investigated. METHODS: To investigate the role of myeloid cell Lgr4 in atherosclerosis development, myeloid cell-specific knockout ( Cre, ) and littermate control () mice were injected intraperitoneally with h-AAV8 and fed a Western diet for 16 weeks. Various in vitro cell-based assays, molecular biology techniques, and immunohistological approaches were used to evaluate the functional roles of macrophage Lgr4 and underlying signaling mechanisms. RESULTS: Oil red O staining of whole aortas and aortic root sections demonstrated reduced atherosclerosis in mice compared with sex-matched mice. However, no changes in circulating monocyte frequencies were detected. Histochemical staining performed on aortic root sections revealed smaller necrotic cores and higher collagen content in mice. Additionally, mice exhibited lower fat mass and blood glucose levels, while plasma total cholesterol was comparable to that of control mice. Further in vitro and ex vivo studies demonstrated reduced lipid accumulation, enhanced efferocytic capacity, a suppressed proinflammatory phenotype, and attenuated expression of different low-density lipoprotein uptake genes in -deficient macrophages. Moreover, knockout macrophages displayed increased cholesterol efflux capacity and reduced activation of oxidized low-density lipoprotein-induced Wnt/β-catenin signaling. CONCLUSIONS: These findings suggest that myeloid cell contributes to atherosclerotic lesion formation via stimulating macrophage lipid accumulation, impairing efferocytic capacity, and promoting a proinflammatory phenotype. Collectively, these results identify macrophage LGR4 as a novel therapeutic target for atherosclerosis.
Pulmonary vascular development requires coordinated growth, remodeling, and specialization of the endothelial network to support airway branching and alveolar formation. Recent advances in single-cell and spatial transcr...Pulmonary vascular development requires coordinated growth, remodeling, and specialization of the endothelial network to support airway branching and alveolar formation. Recent advances in single-cell and spatial transcriptomics have revealed that endothelial cells are organized along a transcriptional arteriovenous spectrum while simultaneously adopting region-specific identities within the capillary bed. In particular, the emergence of distinct alveolar capillary populations, including capillary endothelial cell type 1 and capillary endothelial cell type 2 cells, highlights previously unappreciated heterogeneity. Parallel studies further demonstrate that macrovascular and microvascular identities are influenced by positional context, vessel caliber, and flow-associated transcriptional programs. Together, these insights redefine how endothelial specialization is established during lung development. Here, we review current understanding of pulmonary vascular morphogenesis, endothelial fate specification, and capillary diversification and discuss how emerging imaging platforms may help connect molecular identity with spatial organization and dynamic cellular behavior.
BACKGROUND: Abdominal aortic aneurysm (AAA) rupture is an important cause of death worldwide, with no effective drug therapies currently available. PCSK9 (proprotein convertase subtilisin/kexin type 9) regulates LDL-C (l...BACKGROUND: Abdominal aortic aneurysm (AAA) rupture is an important cause of death worldwide, with no effective drug therapies currently available. PCSK9 (proprotein convertase subtilisin/kexin type 9) regulates LDL-C (low-density lipoprotein-cholesterol) and modulates vascular inflammation, smooth muscle cell apoptosis, and extracellular matrix remodeling, all implicated in AAA pathogenesis. METHODS: We conducted a systematic review and meta-analysis of studies evaluating the effects of PCSK9 upregulation or inhibition on AAA in mouse models. The primary outcome was AAA diameter, with secondary outcomes including lipid and inflammatory markers. Five articles (11 studies, 101 experimental, and 84 control mice) were included. Meta-analysis results were reported as standardized mean difference and 95% CIs. A custom tool, which integrated Cochrane criteria, ARRIVE guidelines, and methods from prior systematic reviews, was used to assess the risk of bias. RESULTS: PCSK9 upregulation significantly increased AAA diameter (standardized mean difference, 1.07 [95% CI, 0.33-1.81]; =0.005) and blood concentrations of total cholesterol, LDL (low-density lipoprotein), and triglycerides while significantly reducing blood concentrations of high-density lipoprotein. PCSK9 upregulation also increased aortic IL (interleukin)-6 and IL1-β concentrations, as assessed by aortic immunohistochemical staining. PCSK9 inhibition significantly reduced AAA diameter (standardized mean difference, -0.97 [95% CI, -1.44 to -0.49]; <0.0001) and blood concentrations of IL-1β, IL-6, and TNF-α (tumor necrosis factor-alpha). Risk of bias was low-to-moderate across studies. CONCLUSIONS: In mouse models, PCSK9 upregulation promoted larger AAAs, while PCSK9 inhibition promoted smaller AAAs. These effects were associated with changes in lipid and inflammatory markers. PCSK9 inhibition may be a target to limit AAA growth.
Vascular and cardiovascular diseases are leading causes of mortality globally. Despite significant progress in elucidating the molecular and cellular mechanisms involved in these conditions, some critical aspects, includ...Vascular and cardiovascular diseases are leading causes of mortality globally. Despite significant progress in elucidating the molecular and cellular mechanisms involved in these conditions, some critical aspects, including complex intercellular interactions and therapeutic efficacy, require further investigation to be fully understood and predicted. This lack of knowledge motivates the development of advanced research methodologies, where bioengineering has contributed significantly. Technological advances in bioengineering have evolved into powerful tools that replicate the molecular and cellular microenvironment of human vascular and cardiac tissues with unprecedented fidelity in vitro and ex vivo. The evolution of conventional 2-dimensional, monocultured cell models into 3-dimensional and mechanically dynamic models that also possess tissue-level cellular and molecular sophistications enables studying vascular pathologies and therapies with promising predictability. Various techniques, such as microphysiological systems, organoids, and bioprinting, are increasingly used and further improved through numerous studies to reconstruct human vascular microenvironment and the associated diseases such as atherosclerosis and thrombosis in vitro. Despite these advancements, there are still challenges with each of these methods in addition to the knowledge gaps left for future research. This review takes a critical approach to comprehensively review existing reports and the most recent progress in the application of cutting-edge in vitro and ex vivo technologies for vascular biology and pathology. More importantly, it highlights the challenges and research gaps that will require future research to be addressed.
Healthcare costs are ever increasing, with impacts across all socioeconomic backgrounds. As a result, financial strain and financial toxicity are a consequences of rising healthcare costs and economic variations, with si...Healthcare costs are ever increasing, with impacts across all socioeconomic backgrounds. As a result, financial strain and financial toxicity are a consequences of rising healthcare costs and economic variations, with significant negative impacts on cardiovascular disease. This review explores financial toxicity and the interplay of net worth, financial mobility, and social determinants of health in cardiovascular disease while also addressing the role of advocacy and policy in public health. Given the significant multidimensional aspects of financial toxicity, understanding its impact on cardiovascular disease is crucial to improving outcomes on a population-wide scale.
BACKGROUND: Local and systemic endothelial dysfunction following traumatic brain injury (TBI) results in secondary cerebral and pulmonary edema, tissue ischemia, and inflammation. However, the underlying mechanism of the...BACKGROUND: Local and systemic endothelial dysfunction following traumatic brain injury (TBI) results in secondary cerebral and pulmonary edema, tissue ischemia, and inflammation. However, the underlying mechanism of the endothelial dysfunction beyond the site of the primary trauma remains poorly understood. Morphologically intact and metabolically active extracellular mitochondria (exMt) accounted for 55.2% of brain-derived extracellular vesicles found in the peripheral blood of mice subjected to severe TBI. This observation led us to investigate the role of exMt in TBI-induced secondary endothelial injury. METHODS: We measured circulating exMt in patients with TBI and mice subjected to TBI and examined the effects of exMt on endothelial cells in vitro and in vivo. Mechanistic studies involved evaluating Cavin-1-dependent endocytosis of exMt and its downstream effects on endothelial cells, including mitophagy activation, lysosomal dysfunction, and apoptosis. The findings were validated in Cavin-1 knockdown endothelial cells and Cavin-1-deficient mice. RESULTS: Here, we report the detection of high levels of exMt in the peripheral blood samples from patients with TBI. These circulating exMt bound to and were endocytosed by endothelial cells via a Cavin-1-dependent pathway. exMt activated endothelial cells, caused vascular leakage, and promoted an inflammatory response in vitro. Furthermore, noninjured mice infused with exMt developed similar changes in the brain and lungs. exMt endocytosed by endothelial cells activated mitophagy and promoted the formation of mitophagosomes but impaired lysosomal function, leading to endothelial cell apoptosis. CONCLUSIONS: Results from this study demonstrate a novel subcellular mechanism for exMt-induced endothelial dysfunction during acute TBI.
Sleep is an active period of profound autonomic fluctuation, cycling between the parasympathetic dominance of nonrapid eye movement sleep and the sympathetic/parasympathetic volatility of rapid eye movement sleep. Sleep-...Sleep is an active period of profound autonomic fluctuation, cycling between the parasympathetic dominance of nonrapid eye movement sleep and the sympathetic/parasympathetic volatility of rapid eye movement sleep. Sleep-disordered breathing, a spectrum of disorders marked by recurrent ventilatory instability and intermittent hypoxia during sleep, particularly obstructive sleep apnea, pathologically amplifies this volatility, transforming sleep into a nightly cascade of severe autonomic and hemodynamic stress. The cardinal features of sleep-disordered breathing, intermittent hypoxia, recurrent arousals, and marked intrathoracic pressure swings, act synergistically to drive chronic, 24-hour sympathetic overactivity, chemoreflex sensitization, and maladaptive neuroplasticity. These effects are mediated at a cellular level by oxidative stress, systemic inflammation, endothelial dysfunction, and neuroendocrine dysregulation. This persistent autonomic reset provides a direct mechanistic link to cardiovascular consequences. It is likely a primary driver of hypertension, blunting the nocturnal blood pressure dip and promoting sustained 24-hour sympathoexcitation. It fosters a proarrhythmic substrate for atrial fibrillation through mechanical stress, which drives atrial remodeling and autonomic conflict. Furthermore, sleep-disordered breathing contributes to myocardial ischemia by increasing myocardial oxygen demand and promoting a prothrombotic state. Beyond chronic disease, sleep-related autonomic shifts can act as acute triggers for malignant arrhythmias in individuals with vulnerable substrates, such as inherited channelopathies, a risk that may be significantly amplified by comorbid sleep-disordered breathing. This review delineates the critical neural and cellular pathways connecting sleep, autonomic dysregulation, and cardiovascular risk.
Arteriovenous malformations (AVMs) are vascular malformations that can occur in virtually all tissues throughout the body, most commonly in the brain, lungs, and cutaneous tissue. AVM pathophysiology is dynamic and multi...Arteriovenous malformations (AVMs) are vascular malformations that can occur in virtually all tissues throughout the body, most commonly in the brain, lungs, and cutaneous tissue. AVM pathophysiology is dynamic and multifactorial with multiple contributing cell types and biological processes. Inflammation and perivascular accumulation of macrophages are well-recognized components of AVM pathophysiology that have been demonstrated for decades in both patient AVM tissue and animal models. Despite the clinical and preclinical data identifying a role for macrophages in AVM pathophysiology, it remains poorly understood how macrophages mechanistically contribute to AVM initiation and progression. Recent single-cell RNA sequencing studies leveraging clinical AVM samples are beginning to shed new light on macrophage diversity in AVM tissue and direct macrophage-mediated effects on endothelial cell signaling pathways. This review will focus on fundamental aspects of AVM pathophysiology, mechanisms of macrophage-mediated vascular remodeling in AVMs, and potential future research directions focused on macrophage-mediated mechanisms in AVM pathophysiology.
Sharma T, Fall T, Sayols-Baixeras S
… +22 more, Maehara A, Maeng M, Kjøller-Hansen L, Engstrøm T, Ben-Yehuda O, Matsumura M, Fröbert O, Persson J, Wiseth R, Larsen AI, Smith JG, Engström G, Ärnlöv J, Borén J, Khamis R, Tsimikas S, Koul S, Rylance R, Ali ZA, James SK, Stone GW, Erlinge D
Arterioscler Thromb Vasc Biol
· 2026 Jun · PMID 42345096
·
Full text
BACKGROUND: Lipidomics, the comprehensive profiling of circulating lipid species, has emerged as a powerful tool to investigate metabolic alterations underlying coronary atherosclerosis. Understanding the mechanisms driv...BACKGROUND: Lipidomics, the comprehensive profiling of circulating lipid species, has emerged as a powerful tool to investigate metabolic alterations underlying coronary atherosclerosis. Understanding the mechanisms driving high-risk vulnerable plaque formation and progression to myocardial infarction remains a key therapeutic priority. This study investigates associations between circulating lipid metabolites and imaging-defined features of vulnerable coronary plaque. METHODS: Following revascularization, patients with myocardial infarction underwent 3-vessel coronary artery imaging with near-infrared spectroscopy and intravascular ultrasound to assess nonflow-limiting plaques for lipid core burden index and plaque burden. Multivariable models evaluated associations between 424 lipid metabolites in plasma, quantified by mass spectrometry, pan-coronary lipid, pan-coronary plaque burden, and high-risk vulnerable plaque measures (maximum lipid core burden index within any 4-mm segment across the entire lesion ≥324.7 and plaque burden ≥70%) in 877 patients. Findings were validated in the SCAPIS study (Swedish Cardiopulmonary Bioimage Study) using coronary computed tomography angiography-based measures of coronary artery calcium score and segment involvement score. RESULTS: We identified 156 significant associations (<0.05) between lipid metabolites and coronary plaque characteristics across 39 metabolic pathways. Sphingomyelins were inversely associated with all plaque metrics, and 1-palmitoyl-2-oleoyl-GPE (16:0/18:1), a phosphatidylethanolamine, was positively associated with all plaque metrics. After correcting for multiple testing, 27 lipid species across 7 pathways remained significant (q<0.05). The majority were linked to pan-coronary lipid burden, with the strongest inverse association observed for sphingomyelin d18:1/22:1, d18:2/22:0, and d16:1/24:1. Similar inverse patterns were seen for select dihydrosphingomyelins and fatty acid dicarboxylates. In contrast, 1-palmitoyl-2-oleoyl-GPE (16:0/18:1) remained positively associated with pan-coronary lipid. In the SCAPIS validation cohort, 19 of the 27 significant lipid associations were successfully replicated (q<0.05). CONCLUSIONS: This study is the first to demonstrate that sphingomyelins are negatively and 1-palmitoyl-2-oleoyl-GPE (16:0/18:1) positively associated with vulnerable coronary plaque features based on multimodality intracoronary imaging in patients with myocardial infarction. Moreover, these associations were validated in a large cohort using coronary computed tomography angiography-derived measures of plaque burden. These novel results may enable the development of new diagnostic and therapeutic strategies.
BACKGROUND: Persistent inflammation is linked to poor outcomes in patients with a history of myocardial infarction. The inflammatory state has been associated with activation of neutrophils as well as with regulatory T-c...BACKGROUND: Persistent inflammation is linked to poor outcomes in patients with a history of myocardial infarction. The inflammatory state has been associated with activation of neutrophils as well as with regulatory T-cell (T) deficiency. The role of T in the regulation of neutrophil survival has been postulated recently. Here, we investigated neutrophil apoptosis along with the potential impact of T on neutrophil apoptosis in patients with postmyocardial infarction chronic coronary syndrome, compared with healthy controls. METHODS: Twenty patients and 19 controls were included. Neutrophil apoptosis was assessed after 5-hour culture with or without IL (interleukin)-10, TNF (tumor necrosis factor), or lipopolysaccharide. Neutrophil phenotype was evaluated through flow cytometry analysis of surface receptors (CD66b and CXCR4) and ex vivo release of cytokines and proteins. The ability of T to induce neutrophil apoptosis was examined in autologous neutrophil-T cocultures. RESULTS: Spontaneous neutrophil apoptosis was significantly delayed in patients compared with controls (10.3% versus 19.2%, =0.025). Also, neutrophils from patients overexpressed CD66b and CXCR4 and were more prone to release proinflammatory mediators. Notably, T induced neutrophil apoptosis in healthy subjects, but not in patients, indicating a loss of T-mediated regulation in the latter. There was no evidence that IL-10 had any influence on neutrophil apoptosis. However, cell-to-cell contact was found essential for T-induced neutrophil apoptosis. CONCLUSIONS: Patients with postmyocardial infarction chronic coronary syndrome display delayed neutrophil apoptosis and a proinflammatory neutrophil phenotype that is resistant to T-mediated apoptosis. Neutrophil dysfunction may contribute to persistent inflammation in patients with postmyocardial infarction chronic coronary syndrome, and as such constitutes a novel therapeutic target.
BACKGROUND: The engraftment of induced cells from human pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) for myocardial infarction therapy is critically hindered by their low cell-cycle activity and survival rate...BACKGROUND: The engraftment of induced cells from human pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) for myocardial infarction therapy is critically hindered by their low cell-cycle activity and survival rates. In this study, we explored the role of the long noncoding RNA activated by DNA damage (NORAD) in enhancing the cell-cycle activity and engraftment of hiPSC-CMs, providing new insights into myocardial repair. METHODS: hiPSC-CMs overexpressing NORAD were generated via lentiviral transduction using a cardiac-specific promoter, whereas NORAD knockdown was achieved by small interfering RNA transfection. The effects of NORAD on cell-cycle activity, nuclear DNA content, nuclear number, maturation, and apoptosis in hiPSC-CMs were examined in vitro using Western blot, reverse transcription quantitative polymerase chain reaction, immunofluorescence, and flow cytometry. In a murine myocardial infarction model, hiPSC-CMs overexpressing NORAD were transplanted into the infarcted myocardium. Engraftment, cell-cycle activity, and infarct size were evaluated by immunofluorescence, and cardiac function was assessed by echocardiography. Furthermore, the molecular mechanisms underlying NORAD-mediated regulation of hiPSC-CM cell-cycle activity were investigated, including its role in exosome-mediated paracrine effects on host cardiomyocytes. RESULTS: NORAD overexpression significantly increased the percentages of Ki67-positive, phosphorylated histone 3-positive, Aurora B-positive, and EdU-positive cells. It also increased the proportion of diploid nuclei and mononucleated cells, induced a trend toward a less mature state, and reduced apoptosis in hiPSC-CMs. Transplantation of hiPSC-CMs overexpressing NORAD improved myocardial repair, with greater cell-cycle activity of engrafted cells and endogenous cardiomyocytes in the myocardial infarction model. Mechanistically, NORAD exerted its effects by sequestering PUM2, an RNA-binding protein, thereby alleviating its translational repression of MASTL, a key regulator of mitotic progression. Moreover, exosomes secreted by hiPSC-CMs overexpressing NORAD promoted the cell-cycle activity of recipient cardiomyocytes, suggesting a possible paracrine contribution to myocardial repair. CONCLUSIONS: NORAD overexpression promoted cell-cycle progression via the PUM2/MASTL mRNA axis. Moreover, exosomes derived from these cells stimulated endogenous cardiomyocyte cell-cycle activity, contributing to myocardial repair. These findings underscore the therapeutic potential of NORAD-modulated hiPSC-CMs for promoting myocardial repair.
Bestepe F, Ghanem GF, Kelly C
… +8 more, Huseynli K, Richards DV, Barber R, Zamary A, Sahu P, Salehi P, Huggins GS, Icli B
Arterioscler Thromb Vasc Biol
· 2026 Jun · PMID 42345092
·
Full text
BACKGROUND: Approximately 25% of patients with type 2 diabetes are at risk of developing diabetic ulcers, which can progress to amputations. A key challenge in diabetic wound healing is impaired angiogenesis. Although SG...BACKGROUND: Approximately 25% of patients with type 2 diabetes are at risk of developing diabetic ulcers, which can progress to amputations. A key challenge in diabetic wound healing is impaired angiogenesis. Although SGLT2 (sodium-glucose transporter 2) inhibitors are known for their cardiovascular and renal benefits, their role in wound healing and angiogenesis, remains incompletely understood. METHODS: We evaluated the effects of empagliflozin, dapagliflozin, and canagliflozin on wound healing in db/db mice by measuring wound closure, granulation tissue thickness, and perfusion. Angiogenesis and proliferation were assessed by CD31 and Ki67 immunostaining. Ex vivo studies used human skin organoids, sprouting assays from human microvessels and murine aortic explants. In vitro studies were performed in human umbilical vein endothelial cells (ECs). RESULTS: Empagliflozin and dapagliflozin significantly improved wound healing, perfusion, angiogenesis, and cell proliferation while canagliflozin showed limited benefit. In human skin organoids and ECs, empagliflozin and dapagliflozin but not canagliflozin improved wound closure, angiogenesis, proliferation, and migration. Sprouting angiogenesis of human vascular explants and mice aorta showed significantly increased branching and junction formation in response to empagliflozin and dapagliflozin. All 3 SGLT2 inhibitors similarly suppressed inflammation and improved EC barrier function, while empagliflozin and dapagliflozin selectively increased tissue remodeling gene expression. Mechanistically, canagliflozin significantly increased AMPK (AMP-activated protein kinase) phosphorylation while decreasing AKT/mTORC1 (mechanistic target of rapamycin complex 1) activation compared with empagliflozin, dapagliflozin. AMPK inhibition with compound C, or dose reduction of canagliflozin, partially restored AKT/mTORC1 signaling and wound closure. CONCLUSIONS: These findings uncover distinct angiogenic effects among SGLT2 inhibitors. Empagliflozin and dapagliflozin promote EC-angiogenic functions through balanced AMPK/AKT/mTORC1 signaling, whereas canagliflozin impaired these processes via excessive AMPK activation and suppression of AKT/mTORC1 signaling. AMPK inhibition or dose reduction restored AKT/mTORC1 signaling and partially rescued wound healing, underscoring the importance of balanced AMPK/AKT/mTORC1 signaling for EC-angiogenic function in diabetic wounds.
CLINICAL PROBLEM: Congenital bleeding disorders stem from genetic defects affecting procoagulant proteins (such as von Willebrand Factor, factor VIII, or factor IX) or platelet proteins (such as integrin αβ or glycoprote...CLINICAL PROBLEM: Congenital bleeding disorders stem from genetic defects affecting procoagulant proteins (such as von Willebrand Factor, factor VIII, or factor IX) or platelet proteins (such as integrin αβ or glycoprotein Ibα). Despite advances in our knowledge of the hemostatic system, there are still gaps in our understanding of the interplay between the various hemostatic actors, limiting the development of efficient therapeutic agents for each of these disorders. RECOMMENDATIONS: Mouse models have a proven record in their use as preclinical tools for the development and testing of therapeutics for bleeding disorders, with several bleeding models being available. However, a lack of standardization for most of these models complicates inter-laboratory comparisons. It is recommended, therefore, that experimental variables are standardized as much as possible to ensure reproducible results, including parameters like temperature and anesthesia. Also, the balance between the use of male and female mice should be considered. SUMMARY OF STRENGTHS AND WEAKNESSES OF MOUSE MODELS OF BLEEDING: Murine hemostasis is relatively similar to human hemostasis, representing a clear strength in translation to the clinic. Among available bleeding models, the tail clip assay is popular for its simplicity, although its standardization might be improved. Other techniques, such as the saphenous vein and laser-induced bleeding models, offer high reproducibility and real-time visualization but require advanced surgical or technological skills. A primary weakness is that most knockout mice do not exhibit the spontaneous hemorrhagic events or joint damage characteristic of human patients. Additionally, species-specific differences can occasionally hamper the testing of therapeutic candidates.
CLINICAL PROBLEM: Venous thromboembolism, encompassing deep vein thrombosis and pulmonary embolism, affects ≈1 to 2 per 1000 individuals annually and represents a major cause of morbidity and mortality worldwide. Despite...CLINICAL PROBLEM: Venous thromboembolism, encompassing deep vein thrombosis and pulmonary embolism, affects ≈1 to 2 per 1000 individuals annually and represents a major cause of morbidity and mortality worldwide. Despite advances in anticoagulation therapy, significant gaps remain in understanding thrombosis resolution, postthrombotic syndrome, and identifying patients at risk for recurrence. Animal models are essential for mechanistic studies and preclinical drug development, yet their translational success has been inconsistent. Critical evaluation of available models is necessary to guide appropriate model selection and improve predictive validity. RECOMMENDATIONS: Select models by the primary biological question and the clinical scenario you want to mimic, then prespecify: (1) flow state (stasis versus reduced flow versus full flow), (2) injury (none/minimal versus chemical/thermal), and (3) end point modality (gross thrombus mass versus imaging volume versus molecular composition versus functional recanalization). Use at least 2 complementary models when claiming generality (eg, a reduced-flow model+a chemical injury model). SUMMARY: This review critically evaluates rodent, large animal, and cellular models of venous thrombosis, addressing their strengths, limitations, reproducibility challenges, and ability to incorporate clinically relevant variables. A comparative analysis with tabular summaries guides researchers in selecting appropriate models while highlighting gaps that must be addressed to improve translational outcomes.