Identificación de medicamentos intravenosos potencialmente irritantes / Identification of potentially irritating intravenous medications

Objetivos: Identificar los medicamentos intravenosos de uso común en el ámbito hospitalario con capacidad de producir daño endotelial. Método: Estudio experimental in vitro. La muestra estuvo formada por 62 medicamentos de uso común en los servicios de urgencias y hospitalización. Las variables estudiadas fueron la osmolaridad y el pH. Posteriormente, en base a esos valores, se determinó la capacidad teórica para provocar daño endotelial, clasificándola en alta, moderada y baja. Resultados: Se analizaron 19 medicamentos para fluidoterapia, 21 antibióticos y 22 medicamentos intravenosos. Las soluciones de glucosa, el bicarbonato 1M y el manitol 10% presentaron una capacidad elevada para provocar irritación venosa. Vancomicina, ciprofloxacino, amiodarona, haloperidol y labetalol mostraron una capacidad irritativa elevada derivada de su pH marcadamente ácido. Los antibióticos, dexketoprofeno, diazepam, digoxina, etomidato, fenitoína, levetiracetam y metamizol presentaron valores extremos de osmolaridad en su presentación reconstituida o sin diluir, y mantuvieron sus valores de tonicidad elevados después de diluirlos en 100ml de suero salino el diazepam, la digoxina y la fenitoína. Conclusiones: Conocer el pH y la osmolaridad de los medicamentos intravenosos permite evaluar su capacidad para provocar daño endotelial. La creación de tablas comprensivas en base a las propiedades químicas de los medicamentos puede constituir una herramienta útil que contribuya a prevenir la flebitis químicamente inducida.(AU)

Aims: To identify commonly used intravenous drugs that may produce endothelial damage. Methods: An experimental research study was performed using a sample of 62 intravenous drugs commonly used in emergency care, pH and osmolarity were measured. Subsequently, based on these values, the theoretical capacity to cause irritation or endovascular damage was determined and classified as high, moderate, and low. Results: Samples from 19 drugs for fluid therapy, 21 antibiotics and 22 drugs for intravenous use were studied. Glucose solutions, sodium bicarbonate 1M and mannitol 10% showed a high capacity to cause venous irritation. Vancomycin, ciprofloxacin, amiodarone, haloperidol, and labetalol solution presented a high capacity for irritation based on their acidic pH. The antibiotics, dexketoprofen, diazepam, digoxin, etomidate, phenytoin, levetiracetam and metamizole also showed high osmotic values in their reconstituted or undiluted presentations. Moreover, osmolarity of diazepam, digoxin and phenytoin remained high despite being diluted in 100mL of saline. Conclusions: Knowing the pH and osmolarity of intravenous drugs allows their capacity to cause endothelial damage to be assessed. The use of comprehensive tables based on the chemical properties of the drugs can be a useful tool to help prevent chemically-induced phlebitis.(AU)

IL-15 induced bystander activation of CD8+ T cells may mediate endothelium injury through NKG2D in Hantaan virus infection.

Introduction: Hantaan virus (HTNV) can cause endothelium injury in hemorrhagic fever with renal syndrome (HFRS) patients. Bystander activation of CD8+ T cells by virus infection has been shown that was involved in host injury, but it is unclear during HTNV infection. This project aimed to study the effect of bystander-activated CD8+ T cell responses in HTNV infection. Methods: The in vitro infection model was established to imitate the injury of endothelium in HFRS patients. Flow cytometry was performed to detect the expression of markers of tetramer+ CD8+ T cells and human umbilical vein endothelial cells (HUVECs). The levels of interleukin-15 (IL-15) in serum and supermanant were detected using ELISA kit. The expression of MICA of HUVECs was respectively determined by flow cytometry and western blot. The cytotoxicity of CD8+ T cells was assessed through the cytotoxicity assay and antibody blocking assay. Results: EBV or CMV-specific CD8+ T cells were bystander activated after HTNV infection in HFRS patients. HTNV-infected HUVECs in vitro could produce high levels of IL-15, which was positively correlated with disease severity and the expression of NKG2D on bystander-activated CD8+ T cells. Moreover, the elevated IL-15 could induce activation of CD122 (IL-15Rß)+NKG2D+ EBV/CMV-specific CD8+ T cells. The expression of IL-15Rα and ligand for NKG2D were upregulated on HTNV-infected HUVECs. Bystander-activated CD8+ T cells could exert cytotoxicity effects against HTNV-infected HUVECs, which could be enhanced by IL-15 stimulation and blocked by NKG2D antibody. Discussion: IL-15 induced bystander activation of CD8+ T cells through NKG2D, which may mediate endothelium injury during HTNV infection in HFRS patients.

Alveolar, Endothelial, and Organ Injury Marker Dynamics in Severe COVID-19.

Rationale: Alveolar and endothelial injury may be differentially associated with coronavirus disease (COVID-19) severity over time. Objectives: To describe alveolar and endothelial injury dynamics and associations with COVID-19 severity, cardiorenovascular injury, and outcomes. Methods: This single-center observational study enrolled patients with COVID-19 requiring respiratory support at emergency department presentation. More than 40 markers of alveolar (including receptor for advanced glycation endproducts [RAGE]), endothelial (including angiopoietin-2), and cardiorenovascular injury (including renin, kidney injury molecule-1, and troponin-I) were serially compared between invasively and spontaneously ventilated patients using mixed-effects repeated-measures models. Ventilatory ratios were calculated for intubated patients. Associations of biomarkers with modified World Health Organization scale at Day 28 were determined with multivariable proportional-odds regression. Measurements and Main Results: Of 225 patients, 74 (33%) received invasive ventilation at Day 0. RAGE was 1.80-fold higher in invasive ventilation patients at Day 0 (95% confidence interval [CI], 1.50-2.17) versus spontaneous ventilation, but decreased over time in all patients. Changes in alveolar markers did not correlate with changes in endothelial, cardiac, or renal injury markers. In contrast, endothelial markers were similar to lower at Day 0 for invasive ventilation versus spontaneous ventilation, but then increased over time only among intubated patients. In intubated patients, angiopoietin-2 was similar (fold difference, 1.02; 95% CI, 0.89-1.17) to nonintubated patients at Day 0 but 1.80-fold higher (95% CI, 1.56-2.06) at Day 3; cardiorenovascular injury markers showed similar patterns. Endothelial markers were not consistently associated with ventilatory ratios. Endothelial markers were more often significantly associated with 28-day outcomes than alveolar markers. Conclusions: Alveolar injury markers increase early. Endothelial injury markers increase later and are associated with cardiorenovascular injury and 28-day outcome. Alveolar and endothelial injury likely contribute at different times to disease progression in severe COVID-19.

Novel biomarker panel measuring endothelial injury identifies patients at risk of coronary artery syndrome and discordance with low-density lipoprotein cholesterol.

BACKGROUND: Individuals with no history of coronary artery disease can develop acute coronary syndrome (ACS), often in the absence of major risk factors including low-density lipoprotein cholesterol (LDL-C). We identified risk factors and biomarkers that can help identify those at discordantly high risk of ACS with normal LDL-C using a novel validated coronary artery disease predictive algorithm (CADPA) incorporating biomarkers of endothelial injury. METHODS: Five-year predicted ACS risk was calculated for 6392 persons using CADPA. Persons were classified as low (<3.5%), intermediate (3.5-<7.5%) or high (≥7.5%) CADPA risk and by LDL-C levels <130 mg/dL (low) and ≥130 mg/dL (high) and whether in the discordantly low LDL-C (but high CADPA risk) or high LDL-C (but low/intermediate CADPA risk) group. Multiple logistic regression identified risk factors and biomarkers that predicted discordance. RESULTS: 31% were classified as low (<3.5%), 27% at intermediate (3.5-<7.5%) and 42% were at high risk (≥7.5%). 28% of subjects were identified in the low LDL discordant risk group (LDL-C< 130 mg/dL but 5-year CADPA predicted risk ≥7.5%) and 19% in the high LDL discordant risk group (LDL-C ≥ 130 mg/dL but 5-year CADPA risk of <7.5%). Diabetes (odds ratio [OR], 2.84 [2.21-3.66]), male sex (OR, 2.83 [2.40-3.35]), family history (OR, 2.23 [1.88-2.64]) and active smoking (OR, 1.99 [1.50-2.62]) predicted low LDL risk discordance more than other risk factors (all P < 0.01). Increased serum soluble FAS, hemoglobin A1c and interleukin-16 were the biomarkers most independently associated with increased risk. CONCLUSIONS: Discordance between LDL-C levels and ACS risk is common. Males with diabetes and a family history of myocardial infarction who are actively smoking may be at highest risk of developing ACS despite controlled LDL-C. Future studies should examine whether using the CADPA can help identify individuals that could benefit from earlier targeting of risk factor modification for the prevention of ACS.

Endothelial damage in septic shock patients as evidenced by circulating syndecan-1, sphingosine-1-phosphate and soluble VE-cadherin: a substudy of ALBIOS.

BACKGROUND: Septic shock is characterized by breakdown of the endothelial glycocalyx and endothelial damage, contributing to fluid extravasation, organ failure and death. Albumin has shown benefit in septic shock patients. Our aims were: (1) to identify the relations between circulating levels of syndecan-1 (SYN-1), sphingosine-1-phosphate (S1P) (endothelial glycocalyx), and VE-cadherin (endothelial cell junctions), severity of the disease, and survival; (2) to evaluate the effects of albumin supplementation on endothelial dysfunction in patients with septic shock. METHODS: This was a retrospective analysis of a multicenter randomized clinical trial on albumin replacement in severe sepsis or septic shock (the Albumin Italian Outcome Sepsis Trial, ALBIOS). Concentrations of SYN-1, S1P, soluble VE-cadherin and other biomarkers were measured on days 1, 2 and 7 in 375 patients with septic shock surviving up to 7 days after randomization. RESULTS: Plasma concentrations of SYN-1 and VE-cadherin rose significantly over 7 days. SYN-1 and VE-cadherin were elevated in patients with organ failure, and S1P levels were lower. SYN-1 and VE-cadherin were independently associated with renal replacement therapy requirement during ICU stay, but only SYN-1 predicted its new occurrence. Both SYN-1 and S1P, but not VE-cadherin, predicted incident coagulation failure. Only SYN-1 independently predicted 90-day mortality. Albumin significantly reduced VE-cadherin, by 9.5% (p = 0.003) at all three time points. CONCLUSION: Circulating components of the endothelial glycocalyx and of the endothelial cell junctions provide insights into severity and progression of septic shock, with special focus on incident coagulation and renal failure. Albumin supplementation lowered circulating VE-cadherin consistently over time. CLINICAL TRIAL REGISTRATION: ALBIOS ClinicalTrials.gov number NCT00707122.

Mitoferrin 2 deficiency prevents mitochondrial iron overload-induced endothelial injury and alleviates atherosclerosis.

Endothelial dysfunction is an early step in the development of atherosclerotic cardiovascular disease. Iron overload can lead to excessive mitochondrial reactive oxygen species (mtROS) production, resulting in mitochondrial dysfunction and vascular endothelial cell (EC) damage. Mitoferrin 2 (Mfrn2) is an iron transporter in the inner mitochondrial membrane. This study aimed to assess whether Mfrn2 and mitochondrial iron overload were involved in atherosclerosis progression and to explore the potential mechanism. We observed significant upregulation of Mfrn2 in the arteries of high-fat diet (HFD)-fed Apolipoprotein E-/- (ApoE-/-) mice and in TNF-α-induced mouse aortic endothelial cells (MAECs). Mfrn2 gene silencing inhibited mitochondrial iron overload, stabilized mitochondrial membrane potential and improved mitochondrial function in TNF-α-induced MAECs. Vascular EC-specific knockdown of Mfrn2 in ApoE-/- mice markedly decreased atherosclerotic lesion formation and the levels of ICAM-1 in aortas and reduced monocyte infiltration into the vascular wall. Furthermore, TNF-α increased the binding of 14-3-3 epsilon (ε) and Mfrn2, preventing Mfrn2 degradation and leading to mitochondrial iron overload in ECs, while 14-3-3ε overexpression increased Mfrn2 stability by inhibiting its ubiquitination. Together, our results reveal that Mfrn2 deficiency attenuates endothelial dysfunction by decreasing iron levels within the mitochondria and mitochondrial dysfunction. These findings may provide new insights into preventive and therapeutic strategies against vascular endothelial dysfunction in atherosclerotic disease.

Influence of burn severity on endothelial glycocalyx shedding following thermal trauma: A prospective observational study.

OBJECTIVE: Severe burns cause hypermetabolic and inflammatory responses are treated with significant volume resuscitation. This study aimed to evaluate correlations between glycocalyx metabolites and the burn size as well as certain clinical parameters such as administered fluid volumes. STUDY DESIGN: Severely burned patients with a total body surface area (TBSA) burned smaller and larger than 20% were included. Clinical parameters including length of stay, mortality, fluid administration and Sequential Organ Failure Assessment (SOFA) score as well as syndecan and heparansulfate, as laboratory parameters for endothelial damage, were obtained. RESULTS: A total of 39 patients (32 males, 7 females) with a mean age at burn of 45 ± 21 years were included. Syndecan levels decreased and heparansulfate levels increased over time. In both heparansulfate and syndecan, there was no significant difference between burns smaller and larger than 20% TBSA at any time point. Syndecan levels at 24 h after burn correlated significantly with IL-10 levels at admission (R = 0.58 and p < 0.05). There were significant linear correlations of %TBSA and cumulative administration of fluids after 24 h on syndecan levels after 48 h. Correlations between clinical parameters and syndecan or heparansulfate levels over time were not found. CONCLUSIONS: This study shows that even though there are moderate correlations with burn size and administered fluid volume, levels of syndecan and heparansulfate are not predictive for clinical outcomes of burned patients in our cohort. Further studies with higher numbers evaluating the effect of large burns on glycocalyx shedding over a longer period of time are needed. Showing significant glycocalyx shedding in large burn including potentially correlations with clinical outcomes may yield new therapeutic targets.

Biphasic effects of autophagy on decompression bubble-induced endothelial injury.

Endothelial dysfunction induced by bubbles plays an important role in decompression sickness (DCS), but the mechanism of which has not been clear. The present study was to investigate the role of autophagy in bubble-induced endothelial injury. Human umbilical vein endothelial cells (HUVECs) were treated with bubbles, autophagy markers and endothelial injury indices were determined, and relationship strengths were quantified. Effects of autophagy inhibitor 3-methyladenine (3-MA) were observed. Bubble contact for 1, 5, 10, 20 or 30 minutes induced significant autophagy with increases in LC3-II/I ratio and Beclin-1, and a decrease in P62, which correlated with bubble contact duration. Apoptosis rate, cytochrome C and cleaved caspase-3 increased, and cell viability decreased following bubble contact for 10, 20 or 30 minutes, but not for 1 or 5 minutes. Injuries in HUVECs were correlated with LC3-II/I ratio and partially reversed by 3-MA in 10, 20 or 30 minutes contact, but worsened in 1 or 5 minutes. Bubble pre-conditioning for 1 minutes resulted in increased cell viability and decreased apoptosis rate compared with no pre-conditioning, and 30-minutes pre-conditioning induced opposing changes, all of which were inhibited by 3-MA. In conclusion, autophagy was involved and played a biphasic role in bubble-induced endothelial injury.

miR-499 released during myocardial infarction causes endothelial injury by targeting α7-nAchR.

The surged systemic vascular inflammation after acute myocardial infarction (AMI) aggravates the atherosclerotic endothelial injury. To explore roles of miR-499 released from cardiomyocytes during AMI in endothelial injury. Using qPCR and ELISA, we discovered that patients with AMI had significantly increased plasma miR-499, which was directly correlated with serum thrombomodulin, a marker for endothelial injury. Plasma of AMI patients, when incubated with human umbilical vein endothelial cells (HUVECs), significantly increased the expression of endothelial injury markers, which could be abrogated by antagomiR-499. In vitro, neonatal rat cardiomyocytes subjected to hypoxia/reoxygenation (HX/R) released miR-499 that could be internalized into rat pulmonary microvascular endothelial cells (RPMECs), worsening the high glucose-induced injury. In silico analysis demonstrated that CHRNA7 encoding α7-nAchR is a target of miR-499, which was validated in cell lines expressing endogenous α7-nAchR. In high glucose-induced RPMECs injury model, miR-499 aggravated, whereas forced CHRNA7 expression ameliorated the injury. Moreover, the perfusate from Langendorff perfused rat heart subjected to HX/R contained higher level of miR-499 that significantly impaired the Bradykinin-mediated endothelium-dependent relaxation in both conduit and resistance arteries, which could be partially abrogated by antagomiR-499. Finally, the correlation between plasma miR-499 and endothelial injury was further confirmed in another cohort of AMI patients. We conclude that miR-499 released from injured cardiomyocytes contributes to the endothelial injury by targeting α7-nAchR. This study implies that miR-499 may serve as a potential target for the treatment of the surged vascular inflammation post-AMI.

Injury induces endothelial to mesenchymal transition in the mouse corneal endothelium in vivo via FGF2.

Purpose: To determine whether the mouse corneal endothelium enters endothelial to mesenchymal transition (EndoMT) following surgical injury in vivo. Methods: The corneal endothelium in anesthetized mice was surgically injured in vivo under direct visualization. The secretion of interleukin-1 beta (IL-1ß) and fibroblast growth factor 2 (FGF2) into the aqueous humor was analyzed with western blotting. The expression of FGF2, Snai1, Zeb1, Col1a1, Col1a2, Fn1, Vim, Cdk2, Ccne1, and Cdh1 was analyzed with semiquantitative RT-PCR in the mouse corneal endothelium ex vivo and in vivo. Knockdown of FGF2 was done using siRNA. Col8a2 was used as a corneal endothelial marker, and Keratocan (Ktcn) was used as a stromal marker. ß-actin was used as a loading control. Results: Sequential expression of IL-1ß and FGF2 was detected in the aqueous humor after surgical injury. FGF2 treatment induced expression of endothelial to mesenchymal transition-related genes including Snai1, and Zeb1 in the mouse ex vivo corneal endothelium. This led to increased expression of Col1a1, Col1a2, Fn1, and Vim and suppression of Cdh1 in a time-dependent manner. Expression of FGF2, Snai1, Zeb1, Col1a1, Col1a2, Fn1, Vim, Cdk2, and Ccne1 was completely abolished by FGF2 siRNA knockdown in the mouse corneal endothelium ex vivo. Surgical injury induced FGF2 expression in the in vivo mouse corneal endothelium. The injury-dependent expression of FGF2, Snai1, Zeb1, Col1a1, Col1a2, Fn1, Vim, Cdk2, and Ccne1 and the suppression of Cdh1 were inhibited by siRNA knockdown of FGF in the mouse corneal endothelium in vivo. Moreover, siRNA knockdown of FGF2 inhibited the formation of the injury-dependent retrocorneal membrane in the in vivo mouse corneal endothelium. Conclusions: These findings suggest that after surgical injury, FGF2 induces the expression of EndoMT-related genes Snai1, Zeb1, Col1a1, Col1a2, Fn1, Vim, Cdk2, and Ccne1 in the mouse corneal endothelium in vivo, similar to the human corneal endothelium ex vivo.

Monocrotaline pyrrole induces pulmonary endothelial damage through binding to and release from erythrocytes in lung during venous blood reoxygenation.

Monocrotaline has been widely used to establish an animal model of pulmonary hypertension, most frequently in rats. An important feature of this model resides in the selectivity of monocrotaline injury toward the pulmonary vascular endothelium versus the systemic vasculature when administrated at standard dosage. The toxic metabolite of monocrotaline, monocrotaline pyrrole, is transported by erythrocytes. This study aimed to reveal whether partial pressure of oxygen of blood determined the binding and release of monocrotaline pyrrole from erythrocytes in rats with one subcutaneous injection of monocrotatline at the standard dosage of 60 mg/kg. Our experiments demonstrated that monocrotaline pyrrole bound to and released from erythrocytes at the physiological levels of partial pressure of oxygen in venous and arterial blood, respectively, and then aggregated on pulmonary artery endothelial cells. Monocrotaline pyrrole-induced damage of endothelial cells was also dependent on partial pressure of oxygen. In conclusion, our results demonstrate the importance of oxygen partial pressure on monocrotaline pyrrole binding to erythrocytes and on aggregation and injury of pulmonary endothelial cells. We suggest that these mechanisms contribute to pulmonary selectivity of this toxic injury model of pulmonary hypertension.

Body Fluids in End-Stage Renal Disease: Statics and Dynamics.

BACKGROUND: Abnormalities in fluid status in hemodialysis (HD) patients are highly prevalent and are related to adverse outcomes. SUMMARY: The inherent discontinuity of the HD procedure in combination with an often compromised cardiovascular response is a major contributor to this phenomenon. In addition, systemic inflammation and endothelial dysfunction are related to extracellular fluid overload (FO). Underlying this relation may be factors such as hypoalbuminemia and an increased capillary permeability, leading to an altered fluid distribution between the blood volume (BV) and the interstitial fluid compartments, compromising fluid removal during dialysis. Indeed, whereas estimates of extracellular volume by bioimpedance spectroscopy are highly predictive of mortality, absolute BV assessed by the saline dilution technique was predictive of intra-dialytic morbidity. Changes in relative BV during HD are positively related to ultrafiltration rate (UFR) and, at least in some studies, negatively to FO. High UFR is also related to changes in central venous oxygen saturation (ScvO2), a marker for tissue perfusion. On the one hand, high UFR and more pronounced declines in ScvO2, but on the other hand, flat relative BV curves are also predictive of mortality; the relation between outcome which statics and dynamics of fluid status appears to be complex. Key Message: While technological developments enable the clinician to monitor statics and dynamics of fluid status and hemodynamics during HD in an accessible way, the role of technology-based interventions needs further study.

Cognitive outcomes after critical illness.

PURPOSE OF REVIEW: There is an increasing realization in the critical care community that persistent cognitive impairment is a common and disabling complication after ICU care. In this review, we discuss the best available information on the magnitude of the problem, its possible mechanisms, risk factors, management strategies and prognosis. RECENT FINDINGS: Estimates of the incidence of persistent cognitive impairment after critical illness vary widely across studies but the most solid prospective information indicates that it may occur in 20-40% of patients discharged from the ICU. From the available evidence, it is difficult to discriminate between de novo cognitive impairment and exacerbation of preexistent cognitive decline. The pathogenesis is multifactorial but inflammatory mechanisms causing derangements of endothelial function and blood-brain barrier integrity might play an important role. Brain atrophy and white matter tract disruption can be structural correlates of the cognitive decline. Prolonged delirium in the ICU is the strongest risk factor for the development of subsequent persistent cognitive impairment. Management strategies are currently limited to those designed to prevent and improve delirium. Cognitive trajectories may vary but a substantial proportion of patients with cognitive impairment 3 months after ICU discharge are still cognitively impaired at 12 months. SUMMARY: Persistent cognitive impairment is a major complication of critical illness. Our knowledge of this problem remains incomplete. Collaborative research is indispensable to improve our understanding of this disabling sequel and to identify ways to prevent it.

Relationships between markers of neurologic and endothelial injury during critical illness and long-term cognitive impairment and disability.

PURPOSE: Neurologic and endothelial injury biomarkers are associated with prolonged delirium during critical illness and may reflect injury pathways that lead to poor long-term outcomes. We hypothesized that blood-brain barrier (BBB), neuronal, and endothelial injury biomarkers measured during critical illness are associated with cognitive impairment and disability after discharge. METHODS: We enrolled adults with respiratory failure and/or shock and measured plasma concentrations of BBB (S100B), neuronal (UCHL1, BDNF), and endothelial (E-selectin, PAI-1) injury markers within 72 h of ICU admission. At 3 and 12 months post-discharge, we assessed participants' global cognition, executive function, and activities of daily living (ADL). We used multivariable regression to determine whether biomarkers were associated with outcomes after adjusting for relevant demographic and acute illness covariates. RESULTS: Our study included 419 survivors of critical illness with median age 59 years and APACHE II score 25. Higher S100B was associated with worse global cognition at 3 and 12 months (P = 0.008; P = 0.01). UCHL1 was nonlinearly associated with global cognition at 3 months (P = 0.02). Higher E-selectin was associated with worse global cognition (P = 0.006 at 3 months; P = 0.06 at 12 months). BDNF and PAI-1 were not associated with global cognition. No biomarkers were associated with executive function. Higher S100B (P = 0.05) and E-selectin (P = 0.02) were associated with increased disability in ADLs at 3 months. CONCLUSIONS: S100B, a marker of BBB and/or astrocyte injury, and E-selectin, an adhesion molecule and marker of endothelial injury, are associated with long-term cognitive impairment after critical illness, findings that may reflect mechanisms of critical illness brain injury.

Passivating Injured Endothelium with Kinexins in Thrombolytic Therapy.

Without conjunctive administration of an anticoagulant, endothelial injury-induced thrombosis is resistant to thrombolysis and prone to re-thrombosis. We hypothesized that co-delivery of recombinant tissue plasminogen activator (rtPA) with annexin V-containing anticoagulants that specifically target the injured endothelium may passivate the thrombogenic elements of the vascular injury site and enhance rtPA-induced thrombolysis. In this study, the effects of conjunctive administration of Kinexins (Kunitz inhibitor-annexin V fusion proteins) with rtPA on thrombolysis were determined in vitro and in vivo. Thromboelastometry showed that both TAP-A (tick anticoagulant peptide-annexin V fusion protein; an inhibitor of factor Xa [FXa] and prothrombinase) and A-6L15 (annexin V-6L15 fusion protein; an inhibitor of tissue factor/FVIIa) exerted concentration-dependent (10-100 nM) effects on clot formation, with TAP-A being several folds more potent than A-6L15 in whole blood. Combination of TAP-A or A-6L15 with rtPA (1 µg/mL) led to decrease in lysis index, suggesting conjunctive enhancement of thrombolysis by combined use of rtPA with TAP-A or A-6L15. In a rat cremaster muscle preparation subjected to photochemical injury, conjunctive administration of rtPA and TAP-A significantly restored tissue perfusion to 56%, which is approximately two fold of that by rtPA or TAP-A alone. Near-infrared fluorescence images demonstrated local retention of a fluorescent A-6L15-S288 at the injury site, suggesting a targeting effect of the fusion protein. Pharmacokinetic analysis showed that 123I-labelled TAP-A and A-6L15 had initial distribution half-lives (T1/2α) of approximately 6 minutes and elimination half-lives (T1/2ß) of approximately 2.3 hours. In conclusion, Kinexins were potentially useful adjunctive agents with rtPA thrombolytic therapy especially for thrombosis induced by endothelial injury.

Translational evidence of prothrombotic and inflammatory endothelial damage in Cushing syndrome after remission.

OBJECTIVE: Sustained evidence from observational studies indicates that after remission of Cushing syndrome (CS) a cardiovascular risk phenotype persists. Here, we performed a translational study in active CS and CS in remission (RCS) to evaluate the subclinical cardiometabolic burden and to explore the direct pro-inflammatory and prothrombotic potential of their sera on the endothelium in an in vitro translational atherothrombotic cell model. PATIENTS: Cross sectional study. The groups were (n = 9/group): I. RCS; II. Active CS (ACS) and III. Controls (CTR), all matched for age, body mass index, sex, without other hormonal deficits. DESIGN: We evaluated in vivo: cardiometabolic profile; endothelial markers (sVCAM-1, NO); endothelial dysfunction (FMD); intima-media thickness and body composition (DEXA). In vitro endothelial cells (EC) were exposed to sera taken from the different subjects to evaluate inflammatory EC response (tisVCAM) and thrombogenicity of the generated extracellular matrix (ECM): von Willebrand factor (VWF) and platelet reactivity. RESULTS: Three of the 9 RCS subjects were on glucocorticoid replacement therapy (GC-RT). Patients on GC-RT had a shorter period of time in stable remission. In vivo analysis ACS showed typically metabolic features, while cardiometabolic markers reached statistical significance for RCS only for Hs-CRP (P < .01). In vitro:EC exposed to ACS and RCS sera displayed increased tisVCAM-1 (P < .01 for ACS and P < .05 for RCS vs CTR), VWF (P < .01 for ACS and P < .05 for RCS vs CTR) and platelet adhesion on ECM (P < .01 for ACC and P < .05 for RCS vs CTR). No statistically significant differences were observed between GC-RT RSC and RCS without GC-RT. CONCLUSIONS: The sera of premenopausal women with CS in remission, without atherothrombotic disease, contain circulatory endothelial deleterious factors with a direct thrombogenic and pro-inflammatory endothelial effect that could increase cardiovascular risk.

HMGB1 contributes to glomerular endothelial cell injury in ANCA-associated vasculitis through enhancing endothelium-neutrophil interactions.

Our previous studies demonstrated that high mobility group box-1 (HMGB1), a typical damage-associated molecular pattern (DAMP) protein, is associated with the disease activity of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Moreover, HMGB1 participates in ANCA-induced neutrophil activation. The current study aimed to investigate whether HMGB1 regulated the interaction between neutrophils and glomerular endothelial cells (GEnC) in the presence of ANCA. Correlation analysis on HMGB1 levels in AAV patients and soluble intercellular cell adhesion molecule-1 (sICAM-1) levels or vascular endothelial growth factor (VEGF) levels, which are markers of endothelial cell activation, was performed. The effect of HMGB1 on neutrophil migration towards GEnC, respiratory burst and degranulation of neutrophils in coculture conditions with GEnC was measured. The activation of neutrophils, the activation and injury of GEnC, and the consequent pathogenic role of injured GEnC were evaluated. Plasma levels of HMGB1 correlated with sICAM-1 and VEGF (r = 0.73, P < 0.01; r = 0.41, P = 0.04) in AAV patients. HMGB1 increased neutrophil migration towards GEnC, as well as respiratory burst and degranulation of neutrophils in the presence of ANCA in the coculture system. In the presence of robust neutrophil activation, GEnC were further activated and injured in the coculture system of GEnC and neutrophils. In addition, injured GEnC could produce TF-positive leuco-endothelial microparticles and endothelin-1 (ET-1), while NF-κB was phosphorylated (S529) in the injured GEnC. Plasma levels of HMGB1 correlated with endothelial cell activation in AAV patients. HMGB1 amplified neutrophil activation and the activation and injury of GEnC in the presence of ANCA.

Shock induced endotheliopathy (SHINE) in acute critical illness - a unifying pathophysiologic mechanism.

One quarter of patients suffering from acute critical illness such as severe trauma, sepsis, myocardial infarction (MI) or post cardiac arrest syndrome (PCAS) develop severe hemostatic aberrations and coagulopathy, which are associated with excess mortality. Despite the different types of injurious "hit", acutely critically ill patients share several phenotypic features that may be driven by the shock. This response, mounted by the body to various life-threatening conditions, is relatively homogenous and most likely evolutionarily adapted. We propose that shock-induced sympatho-adrenal hyperactivation is a critical driver of endothelial cell and glycocalyx damage (endotheliopathy) in acute critical illness, with the overall aim of ensuring organ perfusion through an injured microvasculature. We have investigated more than 3000 patients suffering from different types of acute critical illness (severe trauma, sepsis, MI and PCAS) and have found a potential unifying pathologic link between sympatho-adrenal hyperactivation, endotheliopathy, and poor outcome. We entitled this proposed disease entity, shock-induced endotheliopathy (SHINE). Here we review the literature and discuss the pathophysiology of SHINE.