SLC22A17 as a Cell Death-Linked Regulator of Tight Junctions in Cerebral Ischemia.

BACKGROUND: Beyond neuronal injury, cell death pathways may also contribute to vascular injury after stroke. We examined protein networks linked to major cell death pathways and identified SLC22A17 (solute carrier family 22 member 17) as a novel mediator that regulates endothelial tight junctions after ischemia and inflammatory stress. METHODS: Protein-protein interactions and brain enrichment analyses were performed using STRING, Cytoscape, and a human tissue-specific expression RNA-seq database. In vivo experiments were performed using mouse models of transient focal cerebral ischemia. Human stroke brain tissues were used to detect SLC22A17 by immunostaining. In vitro experiments were performed using human brain endothelial cultures subjected to inflammatory stress. Immunostaining and Western blot were used to assess responses in SLC22A17 and endothelial tight junctional proteins. Water content, dextran permeability, and electrical resistance assays were used to assess edema and blood-brain barrier (BBB) integrity. Gain and loss-of-function studies were performed using lentiviral overexpression of SLC22A17 or short interfering RNA against SLC22A17, respectively. RESULTS: Protein-protein interaction analysis showed that core proteins from apoptosis, necroptosis, ferroptosis, and autophagy cell death pathways were closely linked. Among the 20 proteins identified in the network, the iron-handling solute carrier SLC22A17 emerged as the mediator enriched in the brain. After cerebral ischemia in vivo, endothelial expression of SLC22A17 increases in both human and mouse brains along with BBB leakage. In human brain endothelial cultures, short interfering RNA against SLC22A17 prevents TNF-α (tumor necrosis factor alpha)-induced ferroptosis and downregulation in tight junction proteins and disruption in transcellular permeability. Notably, SLC22A17 could repress the transcription of tight junctional genes. Finally, short interfering RNA against SLC22A17 ameliorates BBB leakage in a mouse model of focal cerebral ischemia. CONCLUSIONS: Using a combination of cell culture, human stroke samples, and mouse models, our data suggest that SLC22A17 may play a role in the control of BBB function after cerebral ischemia. These findings may offer a novel mechanism and target for ameliorating BBB injury and edema after stroke.

The 2022 FASEB Virtual Catalyst Conference on the Cardiac Interatrial Septum and Stroke Risk, December 7, 2022.

There is emerging evidence that the cardiac interatrial septum has an important role as a thromboembolic source for ischemic strokes. There is little consensus on treatment of patients with different cardiac interatrial morphologies or pathologies who have had stroke. In this paper, we summarize the important background, diagnostic, and treatment considerations for this patient population as presented during the Federation of American Societies for Experimental Biology (FASEB) Virtual Catalytic Conference on the Cardiac Interatrial Septum and Stroke Risk, held on December 7, 2022. During this conference, many aspects of the cardiac interatrial septum were discussed. Among these were the embryogenesis of the interatrial septum and development of anatomic variants such as patent foramen ovale and left atrial septal pouch. Also addressed were various mechanisms of injury such as shunting physiologies and the consequences that can result from anatomic variants, as well as imaging considerations in echocardiography, computed tomography, and magnetic resonance imaging. Treatment options including anticoagulation and closure were addressed, as well as an in-depth discussion on whether the left atrial septal pouch is a stroke risk factor. These issues were discussed and debated by multiple experts from neurology, cardiology, and radiology.

Consensus Recommendations for Standardized Data Elements, Scales, and Time Segmentations in Studies of Human Circadian/Diurnal Biology and Stroke.

Increasing evidence indicates that circadian and diurnal rhythms robustly influence stroke onset, mechanism, progression, recovery, and response to therapy in human patients. Pioneering initial investigations yielded important insights but were often single-center series, used basic imaging approaches, and used conflicting definitions of key data elements, including what constitutes daytime versus nighttime. Contemporary methodologic advances in human neurovascular investigation have the potential to substantially increase understanding, including the use of large multicenter and national data registries, detailed clinical trial data sets, analysis guided by individual patient chronotype, and multimodal computed tomographic and magnetic resonance imaging. To fully harness the power of these approaches to enhance pathophysiologic knowledge, an important foundational step is to develop standardized definitions and coding guides for data collection, permitting rapid aggregation of data acquired in different studies, and ensuring a common framework for analysis. To meet this need, the Leducq Consortium International pour la Recherche Circadienne sur l'AVC (CIRCA) convened a Consensus Statement Working Group of leading international researchers in cerebrovascular and circadian/diurnal biology. Using an iterative, mixed-methods process, the working group developed 79 data standards, including 48 common data elements (23 new and 25 modified/unmodified from existing common data elements), 14 intervals for time-anchored analyses of different granularity, and 7 formal, validated scales. This portfolio of standardized data structures is now available to assist researchers in the design, implementation, aggregation, and interpretation of clinical, imaging, and population research related to the influence of human circadian/diurnal biology upon ischemic and hemorrhagic stroke.

Circadian Biology and Stroke.

Circadian biology modulates almost all aspects of mammalian physiology, disease, and response to therapies. Emerging data suggest that circadian biology may significantly affect the mechanisms of susceptibility, injury, recovery, and the response to therapy in stroke. In this review/perspective, we survey the accumulating literature and attempt to connect molecular, cellular, and physiological pathways in circadian biology to clinical consequences in stroke. Accounting for the complex and multifactorial effects of circadian rhythm may improve translational opportunities for stroke diagnostics and therapeutics.

Efficacy and safety of percutaneous patent foramen ovale closure in patients with a hypercoagulable disorder.

BACKGROUND: Transcatheter closure of patent foramen ovale (PFO) in patients with cryptogenic stroke reduces the rate of recurrent events. Although presence of thrombophilia increases the risk for paradoxical emboli through a PFO, such patients were excluded from large randomized trials. OBJECTIVES: We compared the safety and efficacy of percutaneous PFO closure in patients with and without a hypercoagulable state. METHODS: Data from 800 consecutive patients undergoing percutaneous PFO closure in our medical center were analyzed. All patients were independently evaluated by specialists in neurology, cardiology, hematology, and vascular medicine. A post-procedural treatment of at least 3 months of anticoagulation was utilized in patients with thrombophilia. Follow-up events included death, recurrent neurological events, and the need for reintervention for significant residual shunt. RESULTS: A hypercoagulable state was found in 239 patients (29.9%). At median follow-up of 41.9 months, there were no differences in the frequencies of stroke or transient ischemic attack between patients with or without thrombophilia (2.5% in non-hypercoagulable group vs. 3.4% in hypercoagulable group, log-rank test p = 0.35). There were no significant differences in baseline demographics, echocardiographic characteristics, procedural success, or complications between groups. CONCLUSION: Percutaneous PFO closure is a safe and effective therapeutic approach for patients with cryptogenic stroke and an underlying hypercoagulable state.

Residual Shunt After Patent Foramen Ovale Closure and Long-Term Stroke Recurrence: A Prospective Cohort Study.

BACKGROUND: Residual shunt is observed in up to 25% of patients after patent foramen ovale (PFO) closure, but its long-term influence on stroke recurrence currently is unknown. OBJECTIVE: To investigate the association of residual shunt after PFO closure with the incidence of recurrent stroke and transient ischemic attack (TIA). DESIGN: Prospective cohort study comparing stroke or TIA recurrence in patients with and without residual shunt after PFO closure. SETTING: Single hospital center. PARTICIPANTS: 1078 consecutive patients (mean age, 49.3 years) with PFO-attributable cryptogenic stroke who were undergoing percutaneous PFO closure were followed for up to 11 years. MEASUREMENTS: Residual shunt was evaluated by transthoracic echocardiography with saline contrast. Primary outcome was a composite of the first recurrent ischemic stroke or TIA after PFO closure. RESULTS: Compared with complete closure, the presence of residual shunt after PFO closure was associated with an increased incidence of recurrent stroke or TIA: 2.32 versus 0.75 events per 100 patient-years (hazard ratio [HR], 3.05 [95% CI, 1.65 to 5.62]; P < 0.001). This result remained robust after adjustment for important covariates, namely age; study period; device; presence of atrial septal aneurysm, hypertension, hyperlipidemia, diabetes, hypercoagulability, or hypermobile septum; and medication use (HR, 3.01 [CI, 1.59 to 5.69]; P < 0.001). Further stratification based on shunt size revealed that moderate or large residual shunts were associated with a higher risk for stroke or TIA recurrence (HR, 4.50 [CI, 2.20 to 9.20]; P < 0.001); the result for small residual shunts was indeterminate (HR, 2.02 [CI, 0.87 to 4.69]; P = 0.102). LIMITATION: Nonrandomized study with potential unmeasured confounding. CONCLUSION: Among patients undergoing PFO closure to prevent future stroke, the presence of residual shunt, particularly a moderate or large residual shunt, was associated with an increased risk for stroke or TIA recurrence. PRIMARY FUNDING SOURCE: National Institutes of Health.

Effects of aging, hypertension and diabetes on the mouse brain and heart vasculomes.

The emerging concept of the vasculome suggests that microvessels contribute to function and dysfunction in every organ. In the brain, aging and comorbidities such as hypertension and diabetes significantly influence a wide variety of neurodegenerative and cerebrovascular disorders, but the underlying mechanisms are complex and remain to be fully elucidated. Here, we hypothesize that aging, hypertension and diabetes perturb gene networks in the vasculome. Microvascular endothelial cells were isolated from mouse brain and heart, and their transcriptomes were profiled with microarrays. For aging, we compared 5 mo vs 15 mo old C57BL6 male mice. For hypertension, we compared 4 mo old normotensive BPN vs hypertensive BPH male mice. For diabetes, we compared 3 mo old diabetic db/db mice with their matching C57BLKS controls. Four overall patterns arose from these comparative analyses. First, organ differences between brain and heart were larger than effects of age and co-morbidities per se. Second, across all conditions, more genes were altered in the brain vasculome compared with the heart. Third, age, hypertension and diabetes perturbed the brain and heart vasculomes in mostly distinct ways, with little overlap. Fourth, nevertheless, a few common pathways were detected in the brain, expressed mostly as a suppression of immune response. These initial drafts of the brain and heart vasculomes in the context of aging and vascular comorbidities should provide a framework for designing future investigations into potential targets and mechanisms in CNS disease.

Surgical timing in infective endocarditis complicated by intracranial hemorrhage.

Given the growing incidence of infective endocarditis (IE), understanding the risks and benefits of valvular surgery is critical. This decision is particularly complex for the 1 in 10 cases complicated by intracranial hemorrhage (ICH). While guideline recommendations currently favor early surgery in general, delayed intervention of at least 4 weeks is still recommended for patients with ICH. To date, there are no randomized controlled trials that inform management of patients with an indication for surgery but concomitant ICH, and even reported observational data are rare. This paper reviews the current literature on timing of surgery with a specific focus on cases of ICH. It emphasizes a growing body of literature challenging the current paradigm that surgery within 4 weeks is associated with neurologic deterioration and high mortality rates by demonstrating favorable outcomes for patients with pre-operative ICH who undergo early valvular surgery. Based on these data, we propose a practical management algorithm to facilitate decisions on surgical timing in these complicated cases. Since more rigorous evidence may never be available, clinicians should make patient-specific surgical timing decisions that attempt to balance the competing risks of neurologic versus cardiac complications.

A potential gliovascular mechanism for microglial activation: differential phenotypic switching of microglia by endothelium versus astrocytes.

BACKGROUND: Activation of microglia can result in phenotypic and functional diversity. However, the pathways that trigger different states of microglial activation remain to be fully understood. Here, we hypothesized that after injury, astrocytes and endothelium may contribute to a gliovascular switch for microglial activation. METHODS: Astrocytes or cerebral endothelial cells were subjected to oxygen glucose deprivation, then conditioned media were transferred to microglia. The release of TNFα, IL-1ß, IL-10, and IGF-1 was measured using ELISA. Surface markers of CD11b, CD45, CD86, and MHC class II were detected by flow cytometry. mRNA expression of iNOS, CD86, CD206, Arginase1, and transcription factors was measured using real-time PCR. Microglial function including migration and phagocytosis was assessed. Dendritogenesis was determined by counting the number of primary dendrites, secondary dendrites, and dendritic ends in the neurons exposed to either endothelial- or astrocyte-activated microglia. RESULTS: Exposure to conditioned media from oxygen-glucose-deprived cerebral endothelial cells or oxygen-glucose-deprived astrocytes activated microglia into different forms. The endothelium converted ramified microglia into amoeboid shapes; increased the release of TNFα, IL-1ß, and IL-10; decreased IGF-1; upregulated iNOS expression; and inhibited microglial migration and phagocytosis. In contrast, astrocytes increased microglial production of IGF-1, upregulated CD206 expression, and enhanced microglial phagocytosis. These opposing effects of the endothelium versus astrocyte crosstalk partly mirror potentially deleterious versus potentially beneficial microglial phenotypes. Consistent with this idea, endothelial-activated microglia were neurotoxic, whereas astrocyte-activated microglia did not affect neuronal viability but instead promoted neuronal dendritogenesis. CONCLUSION: These findings provide proof of concept that endothelial cells and astrocytes provide differing signals to microglia that influence their activation states and suggest that a gliovascular switch may be involved in the balance between beneficial versus deleterious microglial properties.

Extracellular Mitochondria in Cerebrospinal Fluid and Neurological Recovery After Subarachnoid Hemorrhage.

BACKGROUND AND PURPOSE: Recent studies suggest that extracellular mitochondria may be involved in the pathophysiology of stroke. In this study, we assessed the functional relevance of endogenous extracellular mitochondria in cerebrospinal fluid (CSF) in rats and humans after subarachnoid hemorrhage (SAH). METHODS: A standard rat model of SAH was used, where an intraluminal suture was used to perforate a cerebral artery, thus leading to blood extravasation into subarachnoid space. At 24 and 72 hours after SAH, neurological outcomes were measured, and the standard JC1 (5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazolylcarbocyanineiodide) assay was used to quantify mitochondrial membrane potentials in the CSF. To further support the rat model experiments, CSF samples were obtained from 41 patients with SAH and 27 control subjects. Mitochondrial membrane potentials were measured with the JC1 assay, and correlations with clinical outcomes were assessed at 3 months. RESULTS: In the standard rat model of SAH, extracellular mitochondria was detected in CSF at 24 and 72 hours after injury. JC1 assays demonstrated that mitochondrial membrane potentials in CSF were decreased after SAH compared with sham-operated controls. In human CSF samples, extracellular mitochondria were also detected, and JC1 levels were also reduced after SAH. Furthermore, higher mitochondrial membrane potentials in the CSF were correlated with good clinical recovery at 3 months after SAH onset. CONCLUSIONS: This proof-of-concept study suggests that extracellular mitochondria may provide a biomarker-like glimpse into brain integrity and recovery after injury.

Soluble and catalytically active endothelin converting enzyme-1 is present in cerebrospinal fluid of subarachnoid hemorrhage patients.

Endothelin converting Enzyme-1 (ECE-1) is essential for the production of Endothelin-1 (ET-1), which is associated with vasospasm following subarachnoid hemorrhage (SAH). We have previously demonstrated the presence of a catalytically active soluble form of ECE-1 in the media of endothelial cells. We aimed to determine if this form of ECE-1 exists in vivo, in cerebrospinal fluid (CSF) of SAH patients. We examined CSF taken from SAH subjects for the presence of soluble ECE-1 using a bradykinin based quenched fluorescent substrate assay. We obtained further confirmation by characterizing the CSF mediated cleavage products of BigET-1 and BigET18₋34 (6 µg/ml) using mass spectrometry. The specificity of cleavage was confirmed using the ECE-1 inhibitor CGS35066 5 nmol/L. SAH CSF samples had mean ECE-1 activity of 0.127 ± 0.037 µmols of substrate cleaved/µl of CSF/24 h. The C-terminal peptides generated upon the cleavage of BigET-1 and BigET18₋34 were detected 48 h after incubation of these substrates with CSF. Cleavage of these substrates was inhibited by CGS35066. Results of Western blots also produced strong evidence for the presence of truncated soluble ECE-1 in CSF. These results strongly suggest the presence of a truncated but catalytically active form of ECE-1 in the CSF of SAH subjects. Further studies are necessary to determine the biological significance of soluble ECE-1 in CSF of SAH subjects, including an association with vasospasm after SAH.

Proteomic signatures of serum albumin-bound proteins from stroke patients with and without endovascular closure of PFO are significantly different and suggest a novel mechanism for cholesterol efflux.

BACKGROUND: The anatomy of PFO suggests that it can allow thrombi and potentially harmful circulatory factors to travel directly from the venous to the arterial circulation - altering circulatory phenotype. Our previous publication using high-resolution LC-MS/MS to profile protein and peptide expression patterns in plasma showed that albumin was relatively increased in donor samples from PFO-related than other types of ischemic strokes. Since albumin binds a host of molecules and acts as a carrier for lipoproteins, small molecules and drugs, we decided to investigate the albumin-bound proteins (in a similar sample cohort) in an effort to unravel biological changes and potentially discover biomarkers related to PFO-related stroke and PFO endovascular closure. METHODS: The method used in this study combined albumin immuno-enrichment with high resolution LC-MS in order to specifically capture and quantify the albumin-bound proteins. Subsequently, we measured cholesterol and HDL in a larger, separate cohort of PFO stroke patients, pre and post closure. RESULTS: The results demonstrated that a number of proteins were specifically associated with albumin in samples with and without endovascular closure of the PFO, and that the protein profiles were very different. Eight proteins, typically associated with HDL were common to both sample sets and quantitatively differently abundant. Pathway analysis of the MS results suggested that enhanced cholesterol efflux and reduced lipid oxidation were associated with PFO closure. Measurement of total cholesterol and HDL in a larger cohort of PFO closure samples using a colorimetric assay was consistent with the proteomic predictions. CONCLUSIONS: The collective data presented in this study demonstrate that analysis of albumin-bound proteins could provide a valuable tool for biomarker discovery on the effects of PFO endovascular closure. In addition, the results suggest that PFO endovascular closure can potentially have effects on HDL, cholesterol and albumin-bound ApoA-I abundance, therefore possibly providing benefits in cardioprotective functions.

The role of apolipoprotein E in neurodegeneration and cardiovascular disease.

Apolipoprotein E (ApoE) is an abundant plasma protein that interacts with low density lipoprotein receptors and other proteins, participating in the transport of cholesterol and lipids. Research has revealed many other roles for this multifunctional protein. ApoE is polymorphic and exists in three major isoforms: ApoE2, ApoE3 (the most common isoform) and ApoE4, which differ by only one amino acid, at positions 112 and 158. The altered binding to lipids and receptors by ApoE isoforms E2 and E4 results in an elevated risk for neurological, cerebrovascular and cardiovascular pathologies. Most notably, ApoE4 is associated with an elevated risk (relative to E3) for Alzheimer's disease. The application of mass spectrometry for genotyping and also direct measurement of ApoE protein isoforms is a recent development and is well suited to high-throughput applications. The precise quantification of protein isoforms will allow better characterization of effects resulting from heterozygous APOE genotypes.

Plasma-type gelsolin in subarachnoid hemorrhage: novel biomarker today, therapeutic target tomorrow?

There is growing interest in the potential neuroprotective properties of gelsolin. In particular, plasma-type gelsolin (pGSN) can ameliorate deleterious inflammatory response by scavenging pro-inflammatory signals such as actin and lipopolysaccharide. In a recent issue of Critical Care, Pan and colleagues report an important association between pGSN and subarachnoid hemorrhage (SAH) disease severity, and found pGSN to be a novel and promising biomarker for SAH clinical outcome. Previous research shows pGSN may be actively degraded by neurovascular proteases such as matrix metalloproteinases in the cerebral spinal fluid of SAH patients. Taken together, these results suggest that pGSN is not only a novel marker of SAH clinical outcome, but may also play an active mechanistic role in SAH, and potentially serve as a future therapeutic target.

Microvesicles facilitate the differentiation of mesenchymal stem cells into pancreatic beta-like cells via miR-181a-5p/150-5p.

Transplantation of pancreatic islet cells is a promising strategy for the long-term treatment of type 1 diabetes (T1D). The stem cell-derived beta cells showed great potential as substitute sources of transplanted pancreatic islet cells. However, the current efficiency of stem cell differentiation still cannot match the requirements for clinical transplantation. Here, we report that microvesicles (MVs) from insulin-producing INS-1 cells could induce mesenchymal stem cell (MSC) differentiation into pancreatic beta-like cells. The combination of MVs with small molecules, nicotinamide and insulin-transferrin-selenium (ITS), dramatically improved the efficiency of MSC differentiation. Notably, the function of MVs in MSC differentiation requires their entry into MSCs through giant pinocytosis. The MVs-treated or MVs combined with small molecules-treated MSCs show pancreatic beta-like cell morphology and response to glucose stimulation in insulin secretion. Using high throughput small RNA-sequencing, we found that MVs induced MSC differentiation into the beta-like cells through miR-181a-5p/150-5p. Together, our findings reveal the role of MVs or the MV-enriched miR-181a-5p/150-5p as a class of biocompatible reagents to differentiate MSCs into functional beta-like cells and demonstrate that the combined usage of MVs or miR-181a-5p/150-5p with small molecules can potentially be used in making pancreatic islet cells for future clinical purposes.

Atrial Cardiomyopathy Predicts the Functional Outcome and Mortality in Stroke Patients.

AIM: Atrial cardiomyopathy (ACM) is characterized by atrial dysfunction. This study aims to assess the prognostic significance of ACM in patients with noncardioembolic stroke (NCS). METHODS: Patients with NCS within seven days of onset were prospectively enrolled between January 2019 and December 2020. ACM was defined as either an N-terminal pro-brain natriuretic peptide (NT-pro BNP) ＞250 pg/ml or a P-terminal force in precordial lead V1 (PTFV1) ≥ 5000µV·ms. A poor functional outcome was determined as a score of 3-6 on the modified Rankin Scale (mRS) within a 2-year follow-up period. Logistic regression and Cox regression analyses were employed to examine the relationship between ACM and the long-term prognosis of patients with NCS. RESULTS: A total of 1,346 patients were enrolled, of whom 299 (22.2%) patients were diagnosed with ACM. A total of 207(15.4%) patients experienced a poor functional outcome, and 58 (4.3%) patients died. A multivariate logistic regression analysis indicated that ACM was significantly associated with a poor functional outcome in NCS patients [adjusted odds ratio (aOR): 2.01; 95% confidence interval (CI): 1.42-2.87; p＜0.001]. Additionally, a multivariate Cox regression analysis showed that an NT-pro BNP ＞250 pg/ml was significantly associated with an increased risk of all-cause mortality [adjusted hazard ratio (aHR), 2.51; 95% CI: 1.42-4.43; p=0.001]. CONCLUSIONS: ACM may serve as a novel predictor of a poor long-term functional outcome in patients with NCS. Elevated NT-pro BNP levels (＞250 pg/ml) were found to be associated with a higher risk of all-cause mortality. These findings warrant further validation in multicenter studies.

Increased task-relevant fMRI responsiveness in comatose cardiac arrest patients is associated with improved neurologic outcomes.

Early prediction of the recovery of consciousness in comatose cardiac arrest patients remains challenging. We prospectively studied task-relevant fMRI responses in 19 comatose cardiac arrest patients and five healthy controls to assess the fMRI's utility for neuroprognostication. Tasks involved instrumental music listening, forward and backward language listening, and motor imagery. Task-specific reference images were created from group-level fMRI responses from the healthy controls. Dice scores measured the overlap of individual subject-level fMRI responses with the reference images. Task-relevant responsiveness index (Rindex) was calculated as the maximum Dice score across the four tasks. Correlation analyses showed that increased Dice scores were significantly associated with arousal recovery (P < 0.05) and emergence from the minimally conscious state (EMCS) by one year (P < 0.001) for all tasks except motor imagery. Greater Rindex was significantly correlated with improved arousal recovery (P = 0.002) and consciousness (P = 0.001). For patients who survived to discharge (n = 6), the Rindex's sensitivity was 75% for predicting EMCS (n = 4). Task-based fMRI holds promise for detecting covert consciousness in comatose cardiac arrest patients, but further studies are needed to confirm these findings. Caution is necessary when interpreting the absence of task-relevant fMRI responses as a surrogate for inevitable poor neurological prognosis.

Early insulin glycemic control combined with tPA thrombolysis reduces acute brain tissue damages in a focal embolic stroke model of diabetic rats.

BACKGROUND AND PURPOSE: Therapeutic effects of early insulin glycemic control for poststroke hyperglycemia in combination with tissue-type plasminogen activator (tPA) thrombolytic therapy have not yet been studied but are of great clinical interest. In this study, we tested the effects of insulin plus tPA combination in a model of focal embolic stroke in Type I diabetic rats. METHODS: Streptozotocin was used to produce Type I diabetes in male Wistar rats for 6 weeks and then embolic focal strokes were induced. All rats were treated with insulin or saline at 1 hour followed by tPA or saline at 1.5 hour after stroke. Mortality, infarction, hemispheric swelling, hemorrhagic transformation, and perfusion defects were examined at 24 hours after stroke. Total plasma plasminogen activator inhibitor-1 antigen and activity levels were measured before stroke and 1.5, 3, and 6 hours after stroke by ELISA. RESULTS: Early insulin glycemic control alone or tPA thrombolysis alone had no significant effects on ischemic infarction. However, early insulin glycemic control combined with tPA significantly reduced brain infarction and swelling, ameliorated tPA-associated hemorrhagic transformation, and improved plasma perfusion at 24 hours after stroke. We also found that the combination significantly decreased plasma plasminogen activator inhibitor-1 antigen level at 6 hours and plasminogen activator inhibitor-1 activity at 1.5 and 6 hours after stroke. CONCLUSIONS: Early insulin glycemic control may be beneficial in combination with tPA thrombolysis for ischemic stroke with diabetes mellitus or poststroke hyperglycemia.

Safety, tolerability, and effectiveness of anticoagulation and antiplatelet therapy in hereditary hemorrhagic telangiectasia.

BACKGROUND: Antithrombotic therapy (anticoagulation and antiplatelet therapy) is frequently needed in patients with hereditary hemorrhagic telangiectasia (HHT); however, data describing and guiding its use are very limited. OBJECTIVES: To investigate the safety, tolerability, and effectiveness of antithrombotic therapy in HHT in a cohort large enough to compare agents, evaluate for baseline predictors of premature discontinuation, and evaluate hematologic support requirements and healthcare utilization before and after antithrombitc therapy initiation. METHODS: We performed a multicenter observational cohort study characterizing the outcomes of antithrombic therapy in adults with HHT. RESULTS: A total of 119 patients with HHT with 187 discrete antithrombotic therapy episodes were included. Of these, 59 patients (50%) dose-reduced and/or prematurely discontinued therapy (including 52 patients [44%] who discontinued) due to worsened bleeding complications. Initiation at reduced dose intensity had a similar premature discontinuation rate (49%) as initiation at standard dose intensity (43%). In a multivariable logistic model, a history of gastrointestinal bleeding was associated with 3.25-fold odds of discontinuation (p = .001). Hemoglobin was significantly lower (10.8 g/dL vs 12.2 g/dL, p < .001), and the need for hematologic support (intravenous iron and/or red blood cell transfusion) was significantly higher (29 patients vs 12 patients, p = .004) in the 3 months after antithrombotic therapy initiation vs the 3 months before; emergency department visits and hospital admissions due to bleeding also increased. The rates of dose-reduction and/or premature discontinuation were similar regardless of the anticoagulant class (warfarin, 46%; heparin-based, 48%; direct oral anticoagulants, 44%) or with multiple simultaneous agents (44%) but were slightly lower with single-agent antiplatelet therapy (37%). Thromboembolism despite receiving antithrombotic therapy was common (18 patients, 15%) with varying outcomes. CONCLUSION: Antithrombotic therapy is challenging in HHT, resulting in objectively higher morbidity and health care utilization from worsened bleeding. Discontinuation rates approached 50% regardless of the dose intensity at initiation or type of antithrombotic agent used and were higher in patients with a gastrointestinal bleeding history.