Serum albumin is a specific inhibitor of apoptosis in human endothelial cells

Impact of serum albumin levels on long-term all-cause, cardiovascular, and cardiac mortality in patients with first-onset acute myocardial infarction

BACKGROUND

To evaluate the association of serum albumin (SA) with long-term all-cause, cardiovascular, and cardiac mortality in patients with first-onset acute myocardial infarction (AMI).

METHODS

The cohort study enrolled 2305 patients with first-onset AMI. The median follow-up was of 1088days (3years). Impacts of SA on long-time mortality after AMI were determined using multivariate Cox proportional hazard regression analysis with backward selection.

RESULTS

The patients were divided into three categories by SA tertiles (≤3.62, 3.63-4.08, >4.08g/dl). High tertile group was used as reference, the adjusted HRs for all-cause death were 1.21 (P=0.338) and 1.74 (P=0.003) for intermediate and low tertile, respectively (p-for-trend=0.001); The equivalent values for cardiovascular death were 1.13 (P=0.588) and 1.64 (P=0.022), respectively (p-for-trend=0.009); The corresponding values for cardiac death were 1.07 (P=0.806) and 1.59 (P=0.048), respectively (p-for-trend=0.022). Moreover, adjusted HRs per 1-g/dl decrease in SA concentrations were 1.66 (P=0.001) for all-cause death, 1.47 (P=0.024) for cardiovascular death, and 1.61 (P=0.012) for cardiac death.

CONCLUSIONS

Low SA level (≤3.62g/dl) on admission was an independent predictor of long-term all-cause, cardiovascular, and cardiac mortality in patients with first-onset AMI. There was a dose-response relationship between decreased SA concentrations and increased long-term all-cause, cardiovascular, and cardiac mortality.

Giardia's Epithelial Cell Interaction In Vitro: Mimicking Asymptomatic Infection?

The protozoan parasite Giardia duodenalis is responsible for more than 280 million cases of gastrointestinal complaints ("giardiasis") every year, worldwide. Infections are acquired orally, mostly via uptake of cysts in contaminated drinking water. After transformation into the trophozoite stage, parasites start to colonize the duodenum and upper jejunum where they attach to the intestinal epithelium and replicate vegetatively. Outcome of Giardia infections vary between individuals, from self-limiting to chronic, and asymptomatic to severely symptomatic infection, with unspecific gastrointestinal complaints. One proposed mechanism for pathogenesis is the breakdown of intestinal barrier function. This has been studied by analyzing trans-epithelial electric resistances (TEER) or by indicators of epithelial permeability using labeled sugar compounds in in vitro cell culture systems, mouse models or human biopsies and epidemiological studies. Here, we discuss the results obtained mainly with epithelial cell models to highlight contradictory findings. We relate published studies to our own findings that suggest a lack of barrier compromising activities of recent G. duodenalis isolates of assemblage A, B, and E in a Caco-2 model system. We propose that this epithelial cell model be viewed as mimicking asymptomatic infection. This view will likely lead to a more informative use of the model if emphasis is shifted from aiming to identify Giardia virulence factors to defining non-parasite factors that arguably appear to be more decisive for disease.

Impact of serum albumin levels on long-term outcomes in patients undergoing percutaneous coronary intervention

Epidemiological studies have demonstrated an association between low serum albumin levels and both coronary artery disease (CAD) and mortality. However, the long-term clinical impact of low serum albumin level in patients with CAD undergoing percutaneous coronary intervention (PCI) has not yet been fully investigated. We studied 2860 all-comer patients with CAD who underwent their first PCI and had data available for pre-procedural serum albumin between 2000 and 2011. Patients were assigned to tertiles based on pre-procedural albumin levels. We evaluated the incidence of major adverse cardiac events (MACE), including all-cause death and nonfatal myocardial infarction. Mean albumin level was 4.0 ± 0.5 g/dL. Lower albumin levels were associated with older age, lower body mass index (BMI), and higher prevalences of female sex, ACS and chronic kidney disease (CKD). During the median follow-up period of 7.4 years, Kaplan-Meier curves showed ongoing divergence in rates of MACE among albumin tertiles (albumin <3.8 g/dl: 44.3% vs. 3.8-4.1 g/dl: 38.0% vs. >4.1 g/dl: 22.9%; log-rank p < 0.0001). After adjusting for established cardiovascular risk factors including age, acute coronary syndrome, BMI and CKD, serum albumin levels were significantly associated with incidence of MACE (HR 1.74 per 1-g/dl decrease, 95% CI 1.34-2.26, p < 0.0001) and all-cause mortality (HR 1.74, 95% CI 1.30-2.33, p = 0.0002). Pre-PCI low serum albumin level was associated with worse long-term outcomes, independent of traditional risk factors. Assessing albumin levels may allow risk stratification in patients with CAD undergoing PCI.

Independent and Combined Effects of Serum Albumin and C-Reactive Protein on Long-Term Outcomes of Patients Undergoing Percutaneous Coronary Intervention

BACKGROUND

Both inflammation and malnutrition have been reported to be closely linked to atherosclerosis, especially in patients with chronic kidney disease (CKD). The combined effects of serum albumin and C-reactive protein (CRP) on clinical outcomes after percutaneous coronary intervention (PCI) were investigated.

METHODS AND RESULTS

A total of 2,164 all-comer patients with coronary artery disease who underwent their first PCI and had data available for preprocedural serum albumin and hs-CRP levels between 2000 and 2011 were studied. Patients were assigned to 4 groups according to their median serum albumin and CRP levels (4.1 g/dL and 0.10 mg/dL, respectively). The incidence of major adverse cardiac events (MACE), including all-cause death and non-fatal myocardial infarction (MI), was evaluated. During a median follow-up period of 7.5 years, 331 cases of MACE (15.3%), including 270 deaths and 61 non-fatal MIs, occurred. Kaplan-Meier curves showed that the rates of MACE differed significantly among the groups (log-rank P<0.0001), even stratified by with or without CKD (both log-rank P<0.0001). After adjustment for established cardiovascular risk factors, low serum albumin with high CRP levels was associated with adverse cardiac events (hazard ratio 2.55, 95% confidence interval 1.72-3,88, P<0.0001, high albumin/low CRP group as reference).

CONCLUSIONS

The presence of both low serum albumin and high CRP levels conferred a synergistic adverse effect on the risk for long-term MACE in patients undergoing PCI.

Low Serum Albumin level as a Predictor of Hemorrhage Transformation after Intravenous Thrombolysis in Ischemic Stroke Patients

Serum albumin levels has been shown to predict outcome in ischemic stroke patients. We aimed to investigate the relationship between serum albumin levels and hemorrhagic transformation (HT) after intravenous thrombolysis (IVT) in patients with acute stroke. 428 patients receiving intravenous rt-PA therapy were included from 2013 to 2016 and were categorized into two groups: low level (<35 mmol/L) and normal level (35–55 mmol/L) group. Demographic, clinical and laboratory information, HT and functional outcomes were analyzed. Hemorrhagic transformation was comfirmed by CT scan or MRI within 7 days. The functional outcome was measured by modified Barthel Index and modified Rankin Scale (mRS) at 7 days and 90 days. Patients with lower albumin had significantly higher risk of HT (15.3% vs. 4.2%, P = 0.002) and sICH (6.2% vs. 1.4%, P = 0.03) than those with normal level of albumin. In univariate analysis for HT, atrial fibrillation and level of albumin were identified as significant factors (P < 0.001, P = 0.001 respectively). On multivariate logistic regression analysis, serum albumin level remained independent predictor of HT (OR = 4.369, 95% CI = 1.626–11.742, P = 0.003). No significantly difference were found in the clinical outcome at 7 days and 90 days between two groups (P > 0.05). Low level of serum albumin within 24 hours may be an independent predictor of post-thrombolytic HT.

Repeated Oral Administration of Human Serum Albumin Protects from the Cerebral Ischemia in Rat Brain Following MCAO

Albumin is known to have neuroprotective effects. The protein has a long half-life circulation, and its effects can therefore persist for a long time to aid in the recovery of brain ischemia. In the present study, we investigated the neuroprotective effects of human serum albumin (HSA) on brain hemodynamics. Albumin is administrated using repeated oral gavage to the rodents. Sprague-Dawley rats underwent middle cerebral artery occlusion procedures and served as a stroke model. Afterwards, 25% human serum albumin (1.25 g/kg) or saline (5 ml/kg) was orally administrated for 2 weeks in alternating days. After 2 weeks, the rodents were assessed for levels of brain ischemia. Our testing battery consists of behavioral tests and in vivo optical imaging sessions. Modified neurological severity scores (mNSS) were obtained to assess the levels of ischemia and the effects of HSA oral administration. We found that the experimental group demonstrated larger hemodynamic responses following sensory stimulation than controls that were administered with saline. HSA administration resulted in more significant changes in cerebral blood volume following direct cortical electric stimulation. In addition, the mNSS of the treatment group was lower than the control group. In particular, brain tissue staining revealed that the infarct size was also much smaller with HSA administration. This study provides support for the efficacy of HSA, and that long-term oral administration of HSA may induce neuroprotective effects against brain ischemia.

Risk factors of prognosis after acute kidney injury in hospitalized patients

The risk factors, especially laboratory indicators, of prognosis after acute kidney injury (AKI) remain unclear. We conducted a retrospective survey of Chinese People's Liberation Army General Hospital from January 1, 2012 to December 31, 2012 according to the AKI diagnosis standard issued by Kidney Disease Improving Global Outcomes. The epidemiological features and factors influencing hospital mortality and renal function recovery were evaluated through logistic regression analysis. Among 77 662 cases of hospitalized patients, 1387 suffered from AKI. The incidence rate and mortality of AKI were 1.79% and 14.56%, respectively. Multivariate logistic regression analysis revealed that high AKI stage, age greater than 80 years, neoplastic disease, low cardiac output, increased white blood cell count, and decreased platelet count and serum albumin levels were the risk factors affecting the mortality of AKI patients. Conversely, body mass index between 28 and 34.9 was a protective factor. Increased AKI stage, tumor disease, post-cardiopulmonary resuscitation, and RRT were the risk factors of renal function recovery upon discharge. In addition to traditional risk factors, white blood cell count, platelet count, albumin, and BMI were the predictors of the mortality of AKI patients. No laboratory indicators were found to be the risk factors of renal function recovery in AKI patients.

Time-Dependent Impact of Irreversible Electroporation on Pancreas, Liver, Blood Vessels and Nerves: A Systematic Review of Experimental Studies

Introduction

Irreversible electroporation (IRE) is a novel ablation technique in the treatment of unresectable cancer. The non-thermal mechanism is thought to cause mostly apoptosis compared to necrosis in thermal techniques. Both in experimental and clinical studies, a waiting time between ablation and tissue or imaging analysis to allow for cell death through apoptosis, is often reported. However, the dynamics of the IRE effect over time remain unknown. Therefore, this study aims to summarize these effects in relation to the time between treatment and evaluation.

Methods

A systematic search was performed in Pubmed, Embase and the Cochrane Library for original articles using IRE on pancreas, liver or surrounding structures in animal or human studies. Data on pathology and time between IRE and evaluation were extracted.

Results

Of 2602 screened studies, 36 could be included, regarding IRE in liver (n = 24), pancreas (n = 4), blood vessels (n = 4) and nerves (n = 4) in over 440 animals (pig, rat, goat and rabbit). No eligible human studies were found. In liver and pancreas, the first signs of apoptosis and haemorrhage were observed 1–2 hours after treatment, and remained visible until 24 hours in liver and 7 days in pancreas after which the damaged tissue was replaced by fibrosis. In solitary blood vessels, the tunica media, intima and lumen remained unchanged for 24 hours. After 7 days, inflammation, fibrosis and loss of smooth muscle cells were demonstrated, which persisted until 35 days. In nerves, the median time until demonstrable histological changes was 7 days.

Conclusions

Tissue damage after IRE is a dynamic process with remarkable time differences between tissues in animals. Whereas pancreas and liver showed the first damages after 1–2 hours, this took 24 hours in blood vessels and 7 days in nerves.

Self-assembled albumin nanoparticles as a nanocarrier for aclacinomycin A

This study aimed to reduce the cytotoxicity and improve the targeting of aclacinomycin (ACM) by covalently coupling it with amino-oxyacetic acid (AOA) to generate an active intermediate, AOA-ACM. AOA-ACM was conjugated with self-assembled human serum albumin (HSA) nanoparticles constructed using tris(2-carboxyethyl)phosphine (TCEP) as disulfide bond breaking molecules in an 'opening stage-intermediate-closing stage' route, in which the hydrophobic interaction, interchange of sulfhydryl and hydrogen bond may be the key factors in the assembling process. Conjugation between ACM and albumin nanoparticles was found to occur at an ACM ketone site using ¹H-NMR and ¹³C-NMR matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass analysis indicated that the drug loading efficiency of ACM conjugated with HSA nanoparticles (NPs-ACM) was 7.4% (molar ratio = 6:1). The release of NPs-ACM was pH dependent. In vivo studies indicated that NPs-ACM exhibited fourfold higher tumor targeting capability on S180-tumor-bearing mice compared with the free ACM (p < 0.05). The cytotoxictiy and cardiotoxicity of NPs-ACM was reduced compared with the free ACM. Albumin carrier altered the blood pharmacokinetics and distribution of ACM. Hence, the NPs-ACM prodrug is ideal tumor targeting drug carriers for ACM, and the easy approach developed in this study for active intermediate and prodrug preparation can be applied to other pharmacological substances containing ketone groups. The method of preparing HSA-blank nanoparticles through TCEP reduction could be adopted to improve the water solubility of lipophilic drugs and their tumor-targeting specificity by fabricating HSA-lipophilic drug nanoparticles.

Risk burdens of modifiable risk factors incorporating lipoprotein (a) and low serum albumin concentrations for first incident acute myocardial infarction

Risk burdens of modifiable risk factors incorporating lipoprotein (a) (Lp(a)) and low serum albumin (LSA) concentrations for first incident acute myocardial infarction (AMI) haven’t been studied previously. Cross-sectional study of 1552 cases and 6125 controls was performed for identifying the association of risk factors with first incident AMI and their corresponding population attributable risks (PARs). Modifiable risk factors incorporating LSA and Lp(a) accounted for up to 92% of PAR for first incident AMI. Effects of these risk factors were different in different sexes across different age categories. Overall, smoking and LSA were the 2 strongest risk factors, together accounting for 64% of PAR for first incident AMI. After multivariable adjustment, Lp(a) and LSA accounted for 19% and 41%, respectively, and together for more than a half (54%) of PAR for first incident AMI. Modifiable risk factors incorporating LSA and Lp(a) have accounted for an overwhelmingly large proportion of the risk of first incident AMI, indicating most first incident AMI is preventable. The knowledge of risk burdens for first incident AMI incorporating Lp (a) and LSA may be beneficial for further reducing first incident AMI from a new angle.

The Perioperative Use of Albumin

Human serum albumin (HSA) is the predominant product of hepatic protein synthesis and one of the more abundant plasma proteins. HSA is a monomeric multidomain macromolecule, representing the main determinant of plasma oncotic pressure and the main modulator of fluid distribution between body compartments. HSA displays an essential role in maintaining the integrity of the vascular barrier. HSA is the most important antioxidant capacity of human plasma, in addition to its ability to protect the body from the harmful effects of heavy metals such as iron and copper and reduce their ability to produce reactive oxygen radicals. HSA is the main depot for nitric oxide (NO) transport in the blood. HSA represents the main carrier for fatty acids, affects pharmacokinetics of many drugs, and provides the metabolic modification of some drugs and displays pseudo-enzymatic properties. HSA has been widely used successfully for more than 50 years in many settings of perioperative medicine including hypovolemia, shock, burns, surgical blood loss, sepsis, and acute respiratory distress syndrome (ARDS). Recently, the use of HSA has shown a promising neuroprotective effect in patients with subarachnoid hemorrhage. The most recent evidence-based functions and uses of HSA in the perioperative period are reviewed in this chapter.

Decreased admission serum albumin level is an independent predictor of long-term mortality in hospital survivors of acute myocardial infarction. Soroka Acute Myocardial Infarction II (SAMI-II) project

BACKGROUND

Decreased serum albumin level (SAL) was reported to be associated with increased risk of cardiovascular events and short term-mortality in patients with acute myocardial infarction (AMI).

OBJECTIVES

To evaluate the association between SAL and long-term mortality in AMI hospital survivors.

METHODS

Retrospective analysis of patients admitted in a tertiary medical center for AMI 2002-2012 and discharged alive.

EXCLUSION CRITERIA

active infections, inflammatory diseases, significant liver or kidney failure, malignancy, ejection-fraction <20%, severe heart valvular-disease and missing SAL. SAL was categorized as following: <3.4, 3.4-3.7, 3.7-3.9, 3.9-4.1 and >4.1g/dL. The primary outcome was all-cause mortality for up-to 10-years post-AMI.

RESULTS

Out of 12,535 patients, 8750 were included. Patients with reduced SAL were older, higher rate of women, increased prevalence of severe left ventricular dysfunction, chronic renal failure, diabetes mellitus and ST-elevation AMI, 3-vessel coronary artery disease, and in-hospital complications. While the prevalence of chronic ischemic coronary disease, dyslipidemia, smokers and obesity, was lower. Mortality rates throughout the follow-up period increased as SAL decreased with 17.6%, 24%, 28.5%, 38.6%, and 57.5% for SAL of >4.1, 3.9-4.1, 3.7-3.9, 3.4-3.7 and <3.4g/dL respectively (p-for-trend <0.001). Using the SAL category of >4.1g/dL as the reference group, Adjusted Hazard Ratio values were 1.14 (p=0.107), 1.23 (p=0.007), 1.39 (p<0.001) and 1.70 (p<0.001) for the SAL categories of 3.9-4.1, 3.7-3.9, 3.4-3.7 and <3.4g/dL respectively.

CONCLUSIONS

Decreased SAL on admission, including levels within "normal" clinical range, is significantly associated with long-term all-cause mortality in hospital survivors of AMI with a "dose-response" type association.

Interfacial Self-Assembly of Heparin-Mimetic Multilayer on Membrane Substrate as Effective Antithrombotic, Endothelialization, and Antibacterial Coating

In this study, we design the interfacial self-assembly of heparin-mimetic multilayer on poly(ether sulfone) (PES) membrane, which can endow the substrate with excellent cytocompatibility, highly hemocompatibility and enhanced antibacterial properties. The coated 3D sponge-like multilayer was fabricated by surface engineered layer by layer assembly of sulfonic amino polyether sulfone (SNPES) and quaternized chitosan (QC). The cell morphology observation and viability evaluation suggested that the assembled multilayer coating had remarkable cytocompatibility with endothelial cells due to the synergistic promotion of bovine serum albumin adsorption and heparin-mimetic groups; which further indicated that surface endothelialization could be achieved on the heparin-mimetic multilayer. The systematical tests of antithrombotic and blood activation indicated that the heparin-mimetic multilayer-coated membrane owned significantly suppressed adsorption of bovine serum fibrinogen, platelet adhesion and activation, prolonged clotting times, as well as lower activation of blood complement. Furthermore, the antibacterial test suggested the multilayer coated substrates exhibited obvious inhibition capability for both Escherichia coli and Staphylococcus aureus. Therefore, we believe that the developed SNPES/QC multilayer on PES membrane show great potential as a multifunctional coating toward versatile biomedical applications due to the integrated and highly effective antithrombotic, endothelialization, and antibacterial properties.

Developing drug strategies for the neuroprotective treatment of acute ischemic stroke

Developing new treatment strategies for acute ischemic stroke in the last twenty years has offered some important successes, but also several failures. Most trials of neuroprotective therapies have been uniformly negative to date. Recent research has reported how excitatory amino acids act as the major excitatory neurotransmitters in the cerebral cortex and hippocampus. Furthermore, other therapeutic targets such as free radical scavenger strategies and the anti-inflammatory neuroprotective strategy have been evaluated with conflicting data in animal models and human subjects with acute ischemic stroke. Whereas promising combinations of neuroprotection and neurorecovery, such as citicoline, albumin and cerebrolysin have been tested with findings worthy of further evaluation in larger randomized clinical trials. Understanding the complexities of the ischemic cascade is essential to developing pharmacological targets for acute ischemic stroke in neuroprotective or flow restoration therapeutic strategies.

Preprocedural Albumin Levels and Risk of In-Stent Restenosis After Coronary Stenting With Bare-Metal Stent

In-stent restenosis (ISR) remains a significant clinical problem in patients with coronary artery disease treated with percutaneous coronary intervention. Decreased serum albumin (SA) level is related to an increased risk of cardiovascular events. The aim of the present study was to assess whether SA levels at admission are an independent predictor of ISR in patients undergoing bare-metal stent (BMS) implantation. A total of 341 patients (aged 61 ± 11, 65.4% men) with a history of BMS implantation and a further control coronary angiography due to stable angina pectoris (SAP) were included. The study population was classified into 2 groups: patients with and without ISR. The ISR was observed in 140 (41.1%) patients. We found significantly lower SA levels in patients who developed ISR than in those who did not (3.69 ± 0.41 vs 4.07 ± 0.35 mg/dL,P< .001). Multivariate analysis revealed that SA level (odds ratio 0.109, 95% confidence interval 0.017-0.700,P= .020), stent diameter, reason for stent implantation, and body mass index were independent risk factors for the development of ISR. The SA level at admission is inversely associated with ISR in patients with SAP.

Bolus intravenous 0.9% saline, but not 4% albumin or 5% glucose, causes interstitial pulmonary edema in healthy subjects

Rapid intravenous (iv) infusion of 0.9% saline alters respiratory mechanics in healthy subjects. However, the relative cardiovascular and respiratory effects of bolus iv crystalloid vs. colloid are unknown. Six healthy male volunteers were given 30 ml/kg iv 0.9% saline, 4% albumin, and 5% glucose at a rate of 100 ml/min on 3 separate days in a double-blinded, randomized crossover study. Impulse oscillometry, spirometry, lung volumes, diffusing capacity (DLCO), and blood samples were measured before and after fluid administration. Lung ultrasound B-line score (indicating interstitial pulmonary edema) and Doppler echocardiography indices of cardiac preload were measured before, midway, immediately after, and 1 h after fluid administration. Infusion of 0.9% saline increased small airway resistance at 5 Hz (P = 0.04) and lung ultrasound B-line score (P = 0.01) without changes in Doppler echocardiography measures of preload. In contrast, 4% albumin increased DLCO, decreased lung volumes, and increased the Doppler echocardiography mitral E velocity (P = 0.001) and E-to-lateral/septal e' ratio, estimated blood volume, and N-terminal pro B-type natriuretic peptide (P = 0.01) but not lung ultrasound B-line score, consistent with increased pulmonary blood volume without interstitial pulmonary edema. There were no significant changes with 5% glucose. Plasma angiopoietin-2 concentration increased only after 0.9% saline (P = 0.001), suggesting an inflammatory mechanism associated with edema formation. In healthy subjects, 0.9% saline and 4% albumin have differential pulmonary effects not attributable to passive fluid filtration. This may reflect either different effects of these fluids on active signaling in the pulmonary circulation or a protective effect of albumin.

Chemically-defined albumin-free differentiation of human pluripotent stem cells to endothelial progenitor cells

Human pluripotent stem cell (hPSC)-derived endothelial cells and their progenitors are important for vascular research and therapeutic revascularization. Here, we report a completely defined endothelial progenitor differentiation platform that uses a minimalistic medium consisting of Dulbecco's modified eagle medium and ascorbic acid, lacking of albumin and growth factors. Following hPSC treatment with a GSK-3β inhibitor and culture in this medium, this protocol generates more than 30% multipotent CD34+ CD31+ endothelial progenitors that can be purified to >95% CD34+ cells via magnetic activated cell sorting (MACS). These CD34+ progenitors are capable of differentiating into endothelial cells in serum-free inductive media. These hPSC-derived endothelial cells express key endothelial markers including CD31, VE-cadherin, and von Willebrand factor (vWF), exhibit endothelial-specific phenotypes and functions including tube formation and acetylated low-density lipoprotein (Ac-LDL) uptake. This fully defined platform should facilitate production of proliferative, xeno-free endothelial progenitor cells for both research and clinical applications.

Effect of Puumala hantavirus infection on human umbilical vein endothelial cell hemostatic function: platelet interactions, increased tissue factor expression and fibrinolysis regulator release

Puumala virus (PUUV) infection causes over 5000 cases of hemorrhagic fever in Europe annually and can influence the hemostatic balance extensively. Infection might lead to hemorrhage, while a recent study showed an increased risk of myocardial infarction during or shortly after PUUV infection. The mechanism by which this hantavirus influences the coagulation system remains unknown. Therefore we aimed to elucidate mechanisms explaining alterations seen in primary and secondary hemostasis during PUUV infection. By using low passage PUUV isolates to infect primary human umbilical vein endothelial cells (HUVECs) we were able to show alterations in the regulation of primary- and secondary hemostasis and in the release of fibrinolysis regulators. Our main finding was an activation of secondary hemostasis due to increased tissue factor (TF) expression leading to increased thrombin generation in a functional assay. Furthermore, we showed that during infection platelets adhered to HUVEC and subsequently specifically to PUUV virus particles. Infection of HUVEC with PUUV did not result in increased von Willebrand factor while they produced more plasminogen activator inhibitor type-1 (PAI-1) compared to controls. The PAI-1 produced in this model formed complexes with vitronectin. This is the first report that reveals a potential mechanism behind the pro-coagulant changes in PUUV patients, which could be the result of increased thrombin generation due to an increased TF expression on endothelial cells during infection. Furthermore, we provide insight into the contribution of endothelial cell responses regarding hemostasis in PUUV pathogenesis.

Persistent hypoalbuminemia is a predictor of outcome in cervical spinal cord injury

BACKGROUND CONTEXT

Hypoalbuminemia is associated with increased morbidity and mortality in various clinical settings and several major diseases. Albumin has multiple physiologic properties that could be beneficial in central nervous system injury.

PURPOSE

We sought to determine if albumin is associated with patient outcome after cervical spinal cord injury by conducting a retrospective analysis.

STUDY DESIGN/SETTING

A retrospective study of cervical spinal cord injury (CSCI) patients was conducted to investigate if serum albumin levels and other characteristics influence outcome (mechanical ventilation and death).

PATIENT SAMPLE

A total of 178 consecutive patients were included in the present study.

OUTCOME MEASURES

Demographic data were recorded, including age, gender, smoking history, time from injury to admission, severity of neurologic injury, neurologic level of lesion, mechanism of neurologic injury, Glasgow Coma Score, vitals in the Orthopedic Department, the occurrence of early surgical intervention (48 hours after injury), and daily serum albumin levels.

METHODS

No funds were received in support of this work. No specific conflicts of interest were involved in this article. Serum albumin levels and other characteristics known to influence outcome were included in univariate statistical analyses and the multiple logistic regression model to analyze the relationship with mechanical ventilation and death after cervical injury.

RESULTS

Approximately 41.0% (73/178) of patients had complete spinal cord injury (ASIA A), 36.5% (65/178) of patients required mechanical ventilation, and 8.4% (15/178) of patients died within the first month after injury. Albumin remained lower than 30 g/L for a period of time (≥5 days) in patients with an unfavorable outcome (patients requiring mechanical ventilation or who had died). Multiple logistic regression analysis identified age (>50 years), persistent hypoalbuminemia (<30 g/L and ≥5 days), C5 and above neurologic injury, and ASIA A as predictors for mechanical ventilation. In addition, persistent hypoalbuminemia, ASIA A, and C4 and above neurologic injury were significantly associated with death.

CONCLUSION

Similar to the ASIA scale and neurologic level, persistent hypoalbuminemia seems to be an independent predictor of outcome in patients with CSCI. Thus, a randomized trial assessing albumin in the treatment of cervical spinal cord injury is warranted.

Porous ovalbumin scaffolds with tunable properties: A resource-efficient biodegradable material for tissue engineering applications

Natural materials are promising alternatives to synthetic materials used in tissue engineering applications as they have superior biocompatibility and promote better cell attachment and proliferation. Ovalbumin, a natural polymer found in avian egg white, is an example of a nature-derived material. Despite the availability and reported biocompatibility of ovalbumin, limited research has been carried out to investigate the efficacy of ovalbumin-based scaffolds for adipose tissue engineering applications. Hence, the current study was carried out to investigate the effect of different crosslinkers on ovalbumin scaffold properties as first step towards the development of ovalbumin-based scaffolds for adipose tissue engineering applications. In this study, highly porous three-dimensional scaffolds were fabricated by using three different crosslinkers: glutaraldehyde, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and 1,4-butanediol diglycidyl ether. Results showed that the overall scaffold properties such as morphology, pore size and mechanical properties could be modulated based on the type and concentration of crosslinkers used during the fabrication process. Subsequently, the efficacy of the different scaffolds for supporting cell proliferation was investigated. In vitro degradation was also carried on for the best scaffold based on the mechanical and cellular results. Overall, this study is a demonstration of the viability of ovalbumin-based scaffolds as cell carriers for soft tissue engineering applications.

Intravenous fluids in sepsis: what to use and what to avoid

PURPOSE OF REVIEW

Septic shock is one of the most common and life-threatening conditions afflicting critically ill patients. Intravenous volume resuscitation is considered an initial and very important step in management. The most suitable fluid for volume expansion during septic shock remains unclear. In this review, we focus on the benefits and adverse effects of the most commonly used intravenous fluids in critically ill septic patients.

RECENT FINDINGS

The debate about the benefits of colloids over crystalloids has been ongoing for the last few decades. With recent literature showing apparent harm from the use of hydroxyethyl starches (HESs), and given the growing concerns of adverse renal and acid-base abnormalities associated with 0.9% saline compared with balanced crystalloid solutions, it may be time to change the nature of the 'fluid debate'.

SUMMARY

Crystalloids should still be considered as the first-choice drug for volume resuscitation in patients with septic shock. Colloids such as albumin can be considered in some clinical settings. HES should be avoided. Balanced crystalloids might have an important role to play in the management of septic shock.

Proteome profiling of virus-host interactions of wild type and attenuated measles virus strains

Quantitative gel-based proteomics (2D DIGE coupled to MALDI-TOF/TOF MS) has been used to investigate the effects of different measles virus (MV) strains on the host cell proteome. A549/hSLAM cells were infected either with wild type MV strains, an attenuated vaccine or a multiple passaged Vero cell adapted strain. By including interferon beta treatment as a control it was possible to distinguish between the classical antiviral response and changes induced specifically by the different strains. Of 38 differentially expressed proteins in total (p-value ≤0.05, fold change ≥2), 18 proteins were uniquely modulated following MV infection with up to 9 proteins specific per individual strain. Interestingly, wt strains displayed distinct protein patterns particularly during the late phase of infection. Proteins were grouped into cytoskeleton, metabolism, transcription/translation, immune response and mitochondrial proteins. Bioinformatics analysis revealed mostly changes in proteins regulating cell death and apoptosis. Surprisingly, wt strains affected the cytokeratin system much stronger than the vaccine strain. To our knowledge, this is the first study on the MV-host proteome addressing interstrain differences.

BIOLOGICAL SIGNIFICANCE

In the present study we investigated the host cell proteome upon measles virus (MV) infection. The novelty about this study is the side-by side comparison of different strains from the same virus, which has not been done at the proteome level for any other virus including MV. We used different virus strains including a vaccine strain, wild type isolates derived from MV-infected patients as well as a Vero cell adapted strain, which serves as an intermediate between vaccine and wild type strain. We observed differences between vaccine and wild type strains as well as common features between different wild type strains. Perhaps one of the most surprising findings was that differences did not only occur between wild type and vaccine or Vero cell adapted strains but also between different wild type strains. In fact our study suggests that besides the cytokeratin and the IFN system wild type viruses seem to differ as much among each other than from vaccine strains. Thus our results are suggestive of complex and diverse virus-host interactions which differ considerably between different wild type strains. Our data indicate that interstrain differences are prominent and have so far been neglected by proteomics studies.

Arecoline is cytotoxic for human endothelial cells

BACKGROUND

Oral submucous fibrosis is a pre-malignant fibrotic condition caused by areca nut use and involves reduced mucosal vascularity. Arecoline is the principal areca nut alkaloid and is cytotoxic for epithelium and fibroblasts. Endothelial cell cycle arrest is reported on exposure to arecoline, as is cytotoxicity for endothelial-lung carcinoma hybrid cells. We here describe cytotoxicity for primary human endothelial cultures from seven separate donors.

MATERIALS AND METHODS

Human umbilical vein endothelial cells were exposed to increasing concentrations of arecoline and examined by: phase-contrast microscopy, haemocytometer counts, transmission electron microscopy, lactate dehydrogenase release and the methyl-thiazol-tetrazolium assay.

RESULTS

Vacuolation and detachment of endothelium were observed at and above arecoline concentrations of 333 μg/ml or more. Ultrastructural features of cellular stress were seen after 24-h treatment with 111 μg/ml arecoline and included reduced ribosomal studding of endoplasmic reticulum, increased autophagolysosomal structures, increased vacuolation and reduced mitochondrial cristae with slight swelling. Similar changes were seen at 4 h with arecoline at 333 μg/ml or above, but with more severe mitochondrial changes including increased electron density of mitochondrial matrix and greater cristal swelling, while by 24 h, these cells were frankly necrotic. Haemocytometer counts were paralleled by both lactate dehydrogenase release and the methyl-thiazol-tetrazolium assays.

CONCLUSIONS

Arecoline is cytotoxic via necrosis for endothelium, while biochemical assays indicate no appreciable cellular leakage before death and detachment, as well as no clear effect on mitochondrial function in viable cells. Arecoline toxicity may thus contribute to reduced vascularity in oral submucous fibrosis.

Oleate prevents palmitate-induced mitochondrial dysfunction, insulin resistance and inflammatory signaling in neuronal cells

Elevated circulating levels of saturated free fatty acids (sFFAs; e.g. palmitate) are known to provoke inflammatory responses and cause insulin resistance in peripheral tissue. By contrast, mono- or poly-unsaturated FFAs are protective against sFFAs. An excess of sFFAs in the brain circulation may also trigger neuroinflammation and insulin resistance, however the underlying signaling changes have not been clarified in neuronal cells. In the present study, we examined the effects of palmitate on mitochondrial function and viability as well as on intracellular insulin and nuclear factor-κB (NF-κB) signaling pathways in Neuro-2a and primary rat cortical neurons. We next tested whether oleate preconditioning has a protective effect against palmitate-induced toxicity. Palmitate induced both mitochondrial dysfunction and insulin resistance while promoting the phosphorylation of mitogen-activated protein kinases and nuclear translocation of NF-κB p65. Oleate pre-exposure and then removal was sufficient to completely block subsequent palmitate-induced intracellular signaling and metabolic derangements. Oleate also prevented ceramide-induced insulin resistance. Moreover, oleate stimulated ATP while decreasing mitochondrial superoxide productions. The latter were associated with increased levels of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). Inhibition of protein kinase A (PKA) attenuated the protective effect of oleate against palmitate, implicating PKA in the mechanism of oleate action. Oleate increased triglyceride and blocked palmitate-induced diacylglycerol accumulations. Oleate preconditioning was superior to docosahexaenoic acid (DHA) or linoleate in the protection of neuronal cells against palmitate- or ceramide-induced cytotoxicity. We conclude that oleate has beneficial properties against sFFA and ceramide models of insulin resistance-associated damage to neuronal cells.

Targeting fibroblast-like synovial cells at sites of inflammation with peptide targeted liposomes results in inhibition of experimental arthritis

In this study we examined a synovium-specific targeted liposomal drug delivery system for its ability to localize and release its drug cargo to inflamed joints. Targeted liposomes were tested in vitro for binding to synovial fibroblast like (FLS) and endothelial cells using flow cytometry and in vivo for localization to joints using a rat model of adjuvant induced arthritis (AIA). Targeted liposomes were then loaded with anti-arthritic medications and examined for clinical efficacy in AIA. Targeted liposomes specifically bound to rabbit FLS and human FLS and showed a 7-10 fold increase in vivo localization in affected joints compared to unaffected joints. Histological sections from rats treated with prednisone and a new immunosuppressive peptide CP showed minimal inflammation. This report substantiates the ability of the novel FLS sequence to target liposomal drug delivery and offers an alternative therapeutic approach for the treatment of arthritis.

Bioactivated protein-based porous microcarriers for tissue engineering applications

Lipoaspirate-derived extracellular matrix enrichment was able to provide the necessary cell adhesion receptors and biological factors for improving cell–material interactions of porous OVA microcarriers.

Decreased serum albumin predicts hypertension in a Japanese health screening population

OBJECTIVE

The serum albumin level has been reported to be positively associated with blood pressure in some cross-sectional studies. However, the longitudinal relationships between the serum albumin level and incident hypertension have been poorly studied.

METHODS

The incidence of hypertension was calculated for each quartile of serum albumin in 1,385 normotensive men and 855 normotensive women without cardiovascular disease at baseline who revisited for four years thereafter. The hazard ratios (HRs) of incident hypertension were calculated for each one SD increase in the serum albumin level and for the higher quartiles of serum albumin compared with the lowest quartile adjusted for smoking, alcohol drinking, body mass index, proteinuria, estimated glomerular filtration rate, uric acid, fasting glucose, log triglycerides, log high-sensitivity C-reactive protein, white blood cell count, hemoglobin, and systolic blood pressure.

RESULTS

During four years of follow-up (mean; 3.1 years), 242 men (17.5%) and 89 women (10.4%) developed hypertension. The incidence of hypertension significantly decreased through the quartiles of albumin (p for trend=0.012). The HR (95% confidence interval (CI); p value) of hypertension for each one SD increase in the serum albumin level was 0.779 (0.696-0.872; <0.001). Compared with the lowest quartile of serum albumin, the HRs (95% CIs; p values) of hypertension for the second, third and fourth quartiles were 0.765 (0.574-1.018; 0.066), 0.628 (0.440-0.895; 0.010) and 0.520 (0.364-0.742; <0.001), respectively.

CONCLUSION

A decreased serum albumin level was found to be a significant predictor of hypertension in a Japanese health screening population.

A microfluidic device designed to induce media flow throughout pancreatic islets while limiting shear-induced damage

Pancreatic islets are heavily vascularized in vivo with fenestrated endothelial cells (ECs) to facilitate blood glucose-sensing and endocrine hormone secretion. The close proximity of insulin secreting beta cells and ECs also plays a critical role in modulating the proliferation and survival of both cell types with the mechanisms governing this interaction poorly understood. Isolated islets lose EC morphology and mass over a period of days in culture prohibiting study of this interaction in vitro. The loss of ECs also limits the efficacy of islet transplant revascularization in the treatment of Type 1 diabetes. We previously showed that microfluidically driven flow positively affects beta-cell function and EC survival in culture due to enhanced transport of media into the tissue. However, holding islets stationary in media flow using a dam-wall design also resulted in reduced glucose-stimulated metabolic and Ca(2+) responses at the periphery of the tissue consistent with shear-induced damage. We have now created a device that traps islets into sequential cup-shaped nozzles. This hydrodynamic trap design limits flow velocity around the perimeter of the islet while enhancing media flow through the tissue. We demonstrate the feasibility of this device to dynamically treat and collect effluent from islets. We further show that treating islets in this device enhances EC morphology without reducing glucose-stimulate Ca(2+) responses. These data reveal a microfluidic device to study EC and endocrine cell interaction that can be further leveraged to prime islets prior to transplantation.

Does serum albumin and creatinine predict survival of inpatient palliative care patients?

INTRODUCTION

Low creatinine and albumin are found among the chronically ill patients. This study retrospectively reviewed albumin and creatinine levels for survival in patients upon admission.

METHODS

Records of patients admitted over 2 months were reviewed. Recursive partitioning analysis (RPA) identified cutpoints in albumin and creatinine that predicted survival. Kaplan-Meier survival, Cox proportional hazards, and stepwise Cox analyses identified prognostic factors.

RESULTS

Of 83 patients, 81 were assessable. Variables for worse survival were albumin <3.1 g/dL, creatinine >0.93 mg/dL, and male gender. Albumin by continuous, median, RPA, and tertiles was significant; creatinine by RPA. Hazard ratio for albumin >3.1 was 0.28 (P < .001) and for creatinine >0.91 mg/dL was 1.8 (P = .046).

DISCUSSION AND CONCLUSION

Albumin and creatinine are prognostically important.

Transportation conditions for prompt use of ex vivo expanded and freshly harvested clinical-grade bone marrow mesenchymal stromal/stem cells for bone regeneration

Successful preliminary studies have encouraged a more translational phase for stem cell research. Nevertheless, advances in the culture of human bone marrow-derived mesenchymal stromal/stem cells (hBM-MSC) and osteoconductive qualities of combined biomaterials can be undermined if necessary cell transportation procedures prove unviable. We aimed at evaluating the effect of transportation conditions on cell function, including the ability to form bone in vivo, using procedures suited to clinical application. hBM-MSC expanded in current Good Manufacturing Practice (cGMP) facilities (cGMP-hBM-MSC) to numbers suitable for therapy were transported overnight within syringes and subsequently tested for viability. Scaled-down experiments mimicking shipment for 18 h at 4°C tested the influence of three different clinical-grade transportation buffers (0.9% saline alone or with 4% human serum albumin [HSA] from two independent sources) compared with cell maintenance medium. Cell viability after shipment was >80% in all cases, enabling evaluation of (1) adhesion to plastic flasks and hydroxyapatite tricalcium phosphate osteoconductive biomaterial (HA/β-TCP 3D scaffold); (2) proliferation rate; (3) ex vivo osteogenic differentiation in contexts of 2D monolayers on plastic and 3D HA/β-TCP scaffolds; and (4) in vivo ectopic bone formation after subcutaneous implantation of cells with HA/β-TCP scaffold into NOD/SCID mice. Von Kossa staining was used to assess ex vivo osteogenic differentiation in 3D cultures, providing a quantifiable test of 3D biomineralization ex vivo as a rapid, cost-effective potency assay. Near-equivalent capacities for cell survival, proliferation, and osteogenic differentiation were found for all transportation buffers. Moreover, cGMP-hBM-MSC transported from a production facility under clinical-grade conditions of 4% HSA in 0.9% saline to a destination 18 h away showed prompt adhesion to HA/β-TCP 3D scaffold and subsequent in vivo bone formation. A successfully validated transportation protocol extends the applicability of fresh stem cells involving multicentric trials for regenerative medicine.

Association between Serum Albumin, Insulin Resistance, and Incident Diabetes in Nondiabetic Subjects

BACKGROUND

Serum albumin has been suggested to be associated with insulin resistance. We evaluated the association between serum albumin concentration and insulin resistance. We also investigated whether serum albumin level has an independent effect on the development of diabetes.

METHODS

In our study, 9,029 subjects without diabetes, who underwent comprehensive health check-ups annually for 5 years, were categorized into tertiles based on their serum albumin levels at baseline. The odds ratio (OR) for the prevalence of insulin resistance, defined as the top quartile of homeostasis model assessment of insulin resistance and the presence of impaired fasting glucose and nonalcoholic fatty liver disease, was evaluated cross-sectionally. Also, the hazard ratio (HR) for incident diabetes was estimated longitudinally, according to the baseline albumin tertiles using Cox proportional hazard analysis respectively.

RESULTS

From the lowest to the highest tertile of albumin, the multivariable-adjusted ORs of insulin resistance increased significantly in both men and women. During the mean follow-up period of nearly 4 years, 556 (6.1%) subjects progressed to diabetes. The multivariable-adjusted HR (95% confidence interval [CI]) of diabetes in men were 1, 1.09 (95% CI, 0.86 to 1.40), and 1.10 (95% CI, 0.86 to 1.41), respectively, from the lowest to the highest tertiles of baseline albumin. Corresponding values for women were 1, 1.21 (95% CI, 0.66 to 2.21), and 1.06 (95% CI, 0.56 to 2.02), respectively.

CONCLUSION

Our study showed that increased serum albumin level was associated with insulin resistance. However, serum albumin did not have an independent effect on the development of diabetes.

Hepatitis B virus encoded X protein suppresses apoptosis by inhibition of the caspase-independent pathway

Hepatitis B virus (HBV) encoded X protein (HBx) has been implicated in apoptotic and related pathogenic events during hepatocellular carcinoma. However, the underlying molecular mechanism through which HBx acts is largely unclear. We used tandem affinity purification under mild conditions to gain insight into the HBx interactome in HBV-producing HepG2.2.15 cells and identified 49 proteins by mass spectrometry that are potentially associated with HBx. Two of the key proteins of the caspase-independent apoptosis pathway were newly identified, apoptosis-inducing factor (AIF) and the homologous AMID (AIF-homologue mitochondrion-associated inducer of death). We confirmed the interactions of HBx with AIF and with AMID by reciprocal coimmunoprecipitation experiments, respectively. We observed the expression of HBx-reduced AIF-mediated apoptosis and HBx colocalization with AIF and AMID, principally in the cytoplasm. Furthermore, the elevated cytoplasmic levels of HBx could inhibit mitochondrion-to-nucleus translocation of AIF. Here, we present the first detailed molecular evidence that HBx can repress apoptosis via inhibition of the caspase-independent apoptosis pathway. This inhibition of apoptosis involves the repression of the mitochondrion-to-nucleus translocation of AIF, although tests with AMID were not conclusive. These findings provide important insights into the new mechanism of the apoptosis inhibition by HBV.

Membrane and cytoplasmic marker exchange between malignant neoplastic cells and fibroblasts via intermittent contact: increased tumour cell diversity independent of genetic change

We previously demonstrated that human osteosarcoma cells (SAOS-2) induce contact-dependent apoptosis in endothelium, and expected similar apoptosis in human gingival fibroblasts (h-GF) using SAOS-2 alkaline phosphatase (AP) to identify cells. However, h-GF apoptosis did not occur, despite reduction in AP-negative h-GF number (p < 0.01) and enhancement of this by h-GF TNFα pretreatment (p < 0.01). We suggest that TNFα-enhanced transfer of membrane AP from SAOS-2 to h-GF would explain these data. This idea was investigated using fluorescence prelabelled cells and confocal laser scanning microscopy. Co-cultures of membrane-labelled h-GF (marker-DiO) and SAOS-2 (marker-DiD) generated dual-labelled cells, primarily at the expense of single labelled h-GF (p < 0.001), suggesting predominant membrane transfer from SAOS-2 to h-GF. However, opposite directional transfer predominated when membrane labels were reversed; SAOS-2 further expressed green fluorescent protein (GFP) in cytoplasm and nuclei, and h-GF additionally bore nuclear label (Syto59) (p < 0.001). Cytoplasmic exchange was investigated using h-GF prelabelled with cytoplasmic DDAO-SE and nuclear Syto59, co-cultured with SAOS-2 expressing GFP in cytoplasm and nuclei, and predominant cytoplasmic marker transferred from h-GF to SAOS-2 (p < 0.05). Pretreating h-GF with TNFα increased exchange of membrane markers (p < 0.04) but did not affect either cell surface area profile or circularity. Dual-labelled cells had a morphological phenotype differing from SAOS-2 and h-GF (p < 0.001). Time-lapse microscopy revealed extensive migration of SAOS-2 and cell process contact with h-GF, with the appearance of SAOS-2 indulging in 'cellular sipping' from h-GF. Similar exchange of membrane was seen between h-GF and with other cell lines (melanoma MeIRMu, NM39, WMM175, MM200-B12; osteosarcoma U20S; ovarian carcinoma cells PE01, PE04 and COLO316), while cytoplasmic sharing was also seen in all cell lines other than U20S. We suggest that in some neoplasms, cellular sipping may contribute to phenotypic change and the generation of diverse tumour cell populations independent of genetic change, raising the possibility of a role in tumour progression.

Human albumin prevents 6-hydroxydopamine-induced loss of tyrosine hydroxylase in in vitro and in vivo

Human albumin has recently been demonstrated to protect brain neurons from injury in rat ischemic brain. However, there is no information available about whether human albumin can prevent loss of tyrosine hydroxylase (TH) expression of dopaminergic (DA) neurons induced by 6-hydroxydopamine (6-OHDA) toxicity that is most commonly used to create a rat model of Parkinson's disease (PD). In the present study, two microliters of 1.25% human albumin were stereotaxically injected into the right striatum of rats one day before or 7 days after the 6-OHDA lesion in the same side. D-Amphetamine-induced rotational asymmetry was measured 7 days, 3 and 10 weeks after 6-OHDA lesion. We observed that intrastriatal administration of human albumin significantly reduced the degree of rotational asymmetry. The number of TH-immunoreactive neurons present in the substantia nigra was greater in 6-OHDA lesioned rats following human albumin-treatment than non-human albumin treatment. TH-immunoreactivity in the 6-OHDA-lesioned striatum was also significantly increased in the human albumin-treated rats. To examine the mechanisms underlying the effects of human albumin, we challenged PC12 cells with 6-OHDA as an in vitro model of PD. Incubation with human albumin prevented 6-OHDA-induced reduction of cell viability in PC12 cell cultures, as measured by MTT assay. Furthermore, human albumin reduced 6-OHDA-induced formation of reactive oxygen species (ROS) and apoptosis in cultured PC12 cells, as assessed by flow cytometry. Western blot analysis showed that human albumin inhibited 6-OHDA-induced activation of JNK, c-Jun, ERK, and p38 mitogen-activated protein kinases (MAPK) signaling in PC12 cultures challenged with 6-OHDA. Human albumin may protect against 6-OHDA toxicity by influencing MAPK pathway followed by anti-ROS formation and anti-apoptosis.

In vitro and in vivo anti-angiogenic activities of Panduratin A

BACKGROUND

Targeting angiogenesis has emerged as an attractive and promising strategy in anti-cancer therapeutic development. The present study investigates the anti-angiogenic potential of Panduratin A (PA), a natural chalcone isolated from Boesenbergia rotunda by using both in vitro and in vivo assays.

METHODOLOGY/PRINCIPAL FINDINGS

PA exerted selective cytotoxicity on human umbilical vein endothelial cells (HUVECs) with IC(50) value of 6.91 ± 0.85 µM when compared to human normal fibroblast and normal liver epithelial cells. Assessment of the growth kinetics by cell impedance-based Real-Time Cell Analyzer showed that PA induced both cytotoxic and cytostatic effects on HUVECs, depending on the concentration used. Results also showed that PA suppressed VEGF-induced survival and proliferation of HUVECs. Furthermore, endothelial cell migration, invasion, and morphogenesis or tube formation demonstrated significant time- and dose-dependent inhibition by PA. PA also suppressed matrix metalloproteinase-2 (MMP-2) secretion and attenuated its activation to intermediate and active MMP-2. In addition, PA suppressed F-actin stress fiber formation to prevent migration of the endothelial cells. More importantly, anti-angiogenic potential of PA was also evidenced in two in vivo models. PA inhibited neo-vessels formation in murine Matrigel plugs, and angiogenesis in zebrafish embryos.

CONCLUSIONS/SIGNIFICANCE

Taken together, our study demonstrated the distinctive anti-angiogenic properties of PA, both in vitro and in vivo. This report thus reveals another biological activity of PA in addition to its reported anti-inflammatory and anti-cancer activities, suggestive of PA's potential for development as an anti-angiogenic agent for cancer therapy.

Diet-derived polyphenols inhibit angiogenesis by modulating the interleukin-6/STAT3 pathway

Several epidemiological studies have indicated that abundant consumption of foods from plant origin is associated with a reduced risk of developing several types of cancers. This chemopreventive effect is related to the high content of these foods in phytochemicals, such as polyphenols, that interfere with several processes involved in cancer progression including tumor cell growth, survival and angiogenesis. In addition to the low intake of plant-based foods, increased body mass and physical inactivity have recently emerged as other important lifestyle factors influencing cancer risk, leading to the generation of low-grade chronic inflammatory conditions which are a key process involved in tumor progression. The objectives of the current study are to investigate the inhibitory effects of these polyphenols on angiogenesis triggered by an inflammatory cytokine (IL-6) and to determine the mechanisms underlying this action. We found that, among the tested polyphenols, apigenin and luteolin were the most potent angiogenesis inhibitors through their inhibitory effect on the inflammatory cytokine IL-6/STAT3 pathway. These effects resulted in modulation of the activation of extracellular signal-regulated kinase-1/2 signaling triggered by IL-6, as well as in a marked reduction in the proliferation, migration and morphogenic differentiation of endothelial cells. Interestingly, these polyphenols also modulated the expression of IL-6 signal transducing receptor (IL-6Rα) and the secretion of the extracellular matrix degrading enzyme MMP-2 as well as the expression of suppressor of cytokine signaling (SOCS3) protein. Overall, these results may provide important new information on the role of diet in cancer prevention.

The Albumin in Subarachnoid Hemorrhage (ALISAH) multicenter pilot clinical trial: safety and neurologic outcomes

BACKGROUND AND PURPOSE

Human albumin has been shown to exert neuroprotective effects in animal models of cerebral ischemia and humans with various intracranial pathologies. We investigated the safety and tolerability of 25% human albumin in patients with subarachnoid hemorrhage.

METHODS

The Albumin in Subarachnoid Hemorrhage (ALISAH) Pilot Clinical Trial was an open-label, dose-escalation study. We intended to study 4 different dosages of albumin of increasing magnitude (0.625 g/kg: Tier 1; 1.25 g/kg: Tier 2; 1.875 g/kg: Tier 3; and 2.5 g/kg: Tier 4). Each dosage was to be given to 20 adult patients. Treatment was administered daily for 7 days. We investigated the maximum tolerated dose of albumin based on the rate of severe-to-life-threatening heart failure and anaphylactic reaction and functional outcome at 3 months.

RESULTS

We treated 47 adult subjects: 20 in Tier 1; 20 in Tier 2; and 7 in Tier 3. We found that doses ranging up to 1.25 g/kg/day×7 days were tolerated by patients without major dose-limiting complications. We also found that outcomes trended toward better responses in those subjects enrolled in Tier 2 compared with Tier 1 (OR, 3.0513; CI, 0.6586-14.1367) and with the International Intraoperative Hypothermia for Aneurysm Surgery Trial cohort (OR, 3.1462; CI, 0.9158-10.8089).

CONCLUSIONS

Albumin in doses ranging up to 1.25 g/kg/day×7 days was tolerated by patients with subarachnoid hemorrhage without major complications and may be neuroprotective. Based on these results, planning of the ALISAH II, a Phase III, randomized, placebo-controlled trial to test the efficacy of albumin, is underway.

CLINICAL TRIAL REGISTRATION

URL: http://clinicaltrials.gov. Unique identifier: NCT00283400.

Culturing pancreatic islets in microfluidic flow enhances morphology of the associated endothelial cells

Pancreatic islets are heavily vascularized in vivo with each insulin secreting beta-cell associated with at least one endothelial cell (EC). This structure is maintained immediately post-isolation; however, in culture the ECs slowly deteriorate, losing density and branched morphology. We postulate that this deterioration occurs in the absence of blood flow due to limited diffusion of media inside the tissue. To improve exchange of media inside the tissue, we created a microfluidic device to culture islets in a range of flow-rates. Culturing the islets from C57BL6 mice in this device with media flowing between 1 and 7 ml/24 hr resulted in twice the EC-density and -connected length compared to classically cultured islets. Media containing fluorescent dextran reached the center of islets in the device in a flow-rate-dependant manner consistent with improved penetration. We also observed deterioration of EC morphology using serum free media that was rescued by addition of bovine serum albumin, a known anti-apoptotic signal with limited diffusion in tissue. We further examined the effect of flow on beta-cells showing dampened glucose-stimulated Ca²⁺-response from cells at the periphery of the islet where fluid shear-stress is greatest. However, we observed normal two-photon NAD(P)H response and insulin secretion from the remainder of the islet. These data reveal the deterioration of islet EC-morphology is in part due to restricted diffusion of serum albumin within the tissue. These data further reveal microfluidic devices as unique platforms to optimize islet culture by introducing intercellular flow to overcome the restricted diffusion of media components.

Treatment targets in intracerebral hemorrhage

Intracerebral hemorrhage (ICH) imparts a higher mortality and morbidity than ischemic stroke. The therapeutic interventions that are currently available focus mainly on supportive care and secondary prevention. There is a paucity of evidence to support any one acute intervention that improves functional outcome. This chapter highlights current treatment targets for ICH based on the pathophysiology of the disease.

Investigational therapies for ischemic stroke: neuroprotection and neurorecovery

Stroke is one of the leading causes of death and disability worldwide. Current treatment strategies for ischemic stroke primarily focus on reducing the size of ischemic damage and rescuing dying cells early after occurrence. To date, intravenous recombinant tissue plasminogen activator is the only United States Food and Drug Administration approved therapy for acute ischemic stroke, but its use is limited by a narrow therapeutic window. The pathophysiology of stroke is complex and it involves excitotoxicity mechanisms, inflammatory pathways, oxidative damage, ionic imbalances, apoptosis, angiogenesis, neuroprotection, and neurorestoration. Regeneration of the brain after damage is still active days and even weeks after a stroke occurs, which might provide a second window for treatment. A huge number of neuroprotective agents have been designed to interrupt the ischemic cascade, but therapeutic trials of these agents have yet to show consistent benefit, despite successful preceding animal studies. Several agents of great promise are currently in the middle to late stages of the clinical trial setting and may emerge in routine practice in the near future. In this review, we highlight select pharmacologic and cell-based therapies that are currently in the clinical trial stage for stroke.

Comparison of microsuture, interpositional nerve graft, and laser solder weld repair of the rat inferior alveolar nerve

PURPOSE

Intraosseous repair of nerves involves difficulty of access and there is concern that bone healing may interfere with repair outcomes. The present report describes the effect of 3 separate repair techniques on recovery from section of the rat intraosseous inferior alveolar nerve, with reference to the mental nerve distal and the trigeminal ganglion proximal to the nerve section.

MATERIALS AND METHODS

Unilateral exposure of the inferior alveolar nerves of 28 rats was achieved through bone windows. Nerves were sectioned and rats were assigned to 1 of 4 groups (n = 7): untreated controls, microsuture repair, interpositional nerve grafts from the femoral nerve, or laser solder weld repair. Animals were sacrificed 1 year after surgery for histologic evaluation of the mental nerve, inferior alveolar nerve, and trigeminal ganglion compared with unoperated contralateral nerves.

RESULTS

Compared with the unoperated contralateral nerves, nerve section substantially decreased mental nerve fiber number, mental nerve myelination, mental nerve fiber diameter, inferior alveolar nerve vascularity, trigeminal neuron number, and trigeminal neuron horseradish peroxidase tracer uptake and increased trigeminal ganglion degenerate neurons (P < .001). All 3 forms of repair substantially decreased these effects (P < .05). Interpositional nerve graft was least effective (P < .05). Nonetheless, mental nerve fiber diameter was significantly decreased compared with unsectioned nerves after microsuture and laser solder weld repair (P < .05).

CONCLUSIONS

Intraosseous repair of the inferior alveolar nerve decreases peripheral and central signs of degeneration. Clinical hyperesthesia after repair may reflect a predominance of small fibers after recovery.