Circulating soluble intercellular adhesion molecule-1 (sICAM-1) after exercise-induced muscular damage: Does the use of whole-body cryostimulation influence its concentration in blood?

As soluble intercellular adhesion molecule-1 (sICAM-1) was recently hypothesized to be a key player in the mechanisms involved in exercise-induced muscular damage (EIMD), we investigated its circulating concentration changes in athletes before and after EIMD with and without the use of whole-body cryostimulation (WBC; 3 min at -110 °C) at the exercise end and repeated once a day during 4 days. We previously characterized plasma specimens from 11 endurance athletes who performed twice (randomized crossover design) strenuous running leading to EIMD, followed by passive recovery or WBC. Muscle soreness and inflammatory response were observed in both cases but the use of WBC induced a significant reduction in these responses (PlosOne 2011; 6:e22748). We now found that sICAM-1 concentration slightly increased in both circumstances and remained elevated for 24 h (p < 0.01). However, no significant WBC effect was observed concerning sICAM-1 changes indicating that this compound is not a major player both in EIMD and WBC physiological impacts.

Posttraumatic Stress Disorder Is Associated With Worse Endothelial Function Among Veterans

Background

Current research in behavioral cardiology reveals a significant association between posttraumatic stress disorder (PTSD) and increased risk for cardiovascular disease and mortality; however, the underlying mechanisms remain poorly understood. We hypothesized that patients with PTSD would exhibit endothelial dysfunction, a potential mechanism involved in the development and progression of cardiovascular disease.

Methods and Results

A total of 214 outpatients treated at the San Francisco Veterans Affairs Medical Center underwent tests of endothelial function and evaluation for PTSD. Flow‐mediated vasodilation of the brachial artery was performed to assess endothelial function, and current PTSD status was defined by the PTSD Checklist, based on the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition), with a score ≥40. Multivariable linear regression models were used to estimate the association between PTSD status and endothelial function. Patients with PTSD (n=67) were more likely to be male (99% versus 91%, P=0.04) and to have depression (58% versus 8%, P<0.0001) and were less likely to be on an angiotensin‐converting enzyme inhibitor (17% versus 36%, P=0.007) or β‐blocker treatment (25% versus 41%, P=0.03). Univariate analysis demonstrated that patients with PTSD had significantly lower flow‐mediated vasodilation (5.8±3.4% versus 7.5±3.7%; P=0.003); furthermore, lower flow‐mediated vasodilation was associated with increasing age (P=0.008), decreasing estimated glomerular filtration rate (P=0.003), hypertension (P=0.002), aspirin (P=0.03), and β‐blocker treatments (P=0.01). In multivariable analysis, PTSD remained independently associated with lower flow‐mediated vasodilation (P=0.0005).

Conclusions

After adjusting for demographic, comorbidity, and treatment characteristics, PTSD remained associated with worse endothelial function in an outpatient population. Whether poor endothelial function contributes to the higher risk of cardiovascular disease in patients with PTSD deserves further study.

Vascular adhesion protein-1: Role in human pathology and application as a biomarker

Vascular adhesion protein-1 (VAP-1) is a member of the copper-containing amine oxidase/semicarbazide-sensitive amine oxidase (AOC/SSAO) enzyme family. SSAO enzymes catalyze oxidative deamination of primary amines, which results in the production of the corresponding aldehyde, hydrogen peroxide and ammonium. VAP-1 is continuously expressed as a transmembrane glycoprotein in the vascular wall during development and facilitates the accumulation of inflammatory cells into the inflamed environment in concert with other leukocyte adhesion molecules. The soluble form of VAP-1 is released into the circulation mainly from vascular endothelial cells. Over- and under-expression of sVAP-1 result in alterations of the reported reaction product levels, which are involved in the pathogenesis of multiple human diseases. The combination of enzymatic and adhesion capacities as well as its strong association with inflammatory pathologies makes VAP-1 an interesting therapeutic target for drug discovery. In this article, we will review the general characteristics and biological functions of VAP-1, focusing on its important role as a prognostic biomarker in human pathologies. In addition, the potential therapeutic application of VAP-1 inhibitors will be discussed.

Diagnostic biomarkers differentiating metastatic melanoma patients from healthy controls identified by an integrated MALDI-TOF mass spectrometry/bioinformatic approach

The prognosis of advanced metastatic melanoma (American Joint Committee on Cancer (AJCC) stage IV) remains dismal with a 5-year survival rate of 6-18%. In the present study, an integrated MALDI mass spectrometric approach combined with artificial neural networks (ANNs) analysis and modeling has been used for the identification of biomarker ions in serum from stage IV melanoma patients allowing the discrimination of metastatic disease from healthy status with high specificities of 92% for protein ions and 100% for peptide biomarkers. Our ANNs model also correctly classified 98% of a blind validation set of AJCC stage I melanoma samples as nonstage IV samples, emphasizing the power of the newly defined biomarkers to identify patients with late-stage metastatic melanoma. Sequence analysis identified peptides derived from metastasis-associated proteins; alpha 1-acid glycoprotein precursor-1/2 (AAG-1/2) and complement C3 component precursor-1 (CCCP-1). Furthermore, quantitation of serum AAG by an immunoassay showed a significant (p<0.001) increase in AAG serum concentration in stage IV patients in comparison with healthy volunteers; moreover; the quantity of AAG plotted against MALDI-MS peak intensity classified the groups into two distinct clusters. Ongoing studies of other disease stages will provide evidence whether our strategy is sufficiently robust to give rise to stage-specific protein/peptide signatures in melanoma.

Research on Psychoneuroimmunology: Does Stress Influence Immunity and Cause Coronary Artery Disease?

This review addresses the importance of psychoneuroimmunology (PNI) studies in understanding the role of acute and chronic psychological stressors on the immune system and development of coronary artery disease (CAD). Firstly, it illustrates how psychological stressors change endothelial function and lead to chemotaxis. Secondly, acute psychological stressors lead to leukocytosis, increased natural killer cell cytotoxicity and reduced proliferative response to mitogens while chronic psychological stressors may lead to adverse health effects. This will result in changes in cardiovascular function and development of CAD. Thirdly, acute and chronic psychological stressors will increase haemostatic factors and acute phase proteins, possibly leading to thrombus formation and myocardial infarction. The evidence for the effects of acute and chronic psychological stress on the onset and progression of CAD is consistent and convincing. This paper also highlights potential research areas and implications of early detection of immunological changes and cardiovascular risk in people under high psychological stress. Key words: Cardiovascular, Inflammation, Psychoneuroimmunology, Stress

Measures of endothelial dysfunction in plasma of patients with posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) confers an increased cardiovascular risk. In 14 otherwise healthy patients with PTSD and in 14 age- and gender-matched non-PTSD controls, we investigated whether the categorical diagnosis of PTSD and severity of PTSD symptom clusters (i.e. re-experiencing, avoidance, arousal, and overall score) would be associated with plasma concentrations of three markers of endothelial dysfunction [soluble tissue factor (sTF), von Willebrand factor (VWF), and soluble intercellular adhesion molecule (sICAM)-1]. Compared with controls, patients had significantly higher sTF; this difference became nonsignificant when controlling for psychological distress. VWF and sICAM-1 levels were not significantly different between patients and controls. In the entire sample virtually all PTSD symptom clusters correlated significantly and positively with sTF and VWF but not with sICAM-1. The correlation between symptoms of re-experiencing and sTF was significantly different between patients and controls. Controlling for symptoms of anxiety and depression (i.e. psychological distress) rendered most associations between PTSD symptom clusters and sTF nonsignificant, whereas controlling for age retained significance of associations with VWF. Posttraumatic stress showed a continuous relationship with sTF and VWF, with the former relationship being partly affected by psychological distress. This suggests one mechanism by which posttraumatic stress could contribute to atherosclerosis.

Cellular Adhesion Molecules in Healthy Subjects: Short Term Variations and Relations to Flow Mediated Dilation

The objective was primarily to describe short term intra-individual variation in serum levels of soluble adhesion molecules (sCAMs: E-selectin, P-selectin, intercellular adhesion molecule-1(sICAM-1) and vascular cellular adhesion molecule-1(sVCAM-1)) in healthy subjects. Secondly, sCAMs were correlated to brachial artery flow mediated vasodilation (FMD).

Forty healthy subjects aged 24–66 years had sCAMs measured twice with 4 week intervals and short-term intra-individual variation was estimated as variation in the paired measurements after correcting for the analytical precision of the used method. At baseline, brachial FMD was measured.

No difference was observed in mean sCAMs in the whole study group. Estimated intra-subject variations in sCAMs were 7.6–11.3%. In a regression analysis, significant negative association was found between sE-selectin and FMD after controlling for possible confounders (p < 0.04) while no significant correlation could be demonstrated between the other sCAMs and FMD.

In conclusion, short term intra-individual variations in sCAMs were 7.6–11.3% in healthy subjects. We also found a significant negative association between sE-selectin and FMD, indicating an possible association between inflammation and dysfunction of the vascular endothelium; however further studies are required to confirm this preliminary finding.

Relation of nocturnal blood pressure dipping to cellular adhesion, inflammation and hemostasis

BACKGROUND

Subjects who fail to dip their nocturnal blood pressure (BP) are at substantially increased risk for cardiovascular diseases. The pathogenetic mechanisms of this relationship have not been elucidated. We investigated whether non-dipping would relate to procoagulant and proinflammatory activity.

DESIGN

Study participants were 76 unmedicated normotensive and hypertensive subjects (44 male, 32 female; 41 white, 35 black; mean age, 36 +/- 8 years) who underwent 24-h outpatient ambulatory BP monitoring. Based on whether their average nocturnal systolic BP relative to their average daytime systolic BP declined by less than 10%, 34 subjects were categorized as non-dippers. D-dimer, plasminogen activator inhibitor-1, von Willebrand factor, soluble intercellular adhesion molecule-1, and interleukin-6 were measured in plasma.

RESULTS

Multivariate analyses showed that D-dimer (median/interquartile range, 242/162-419 ng/ml versus 175/132-254 ng/ml; P=0.041), plasminogen activator inhibitor-1 (36/19-61 ng/ml versus 17/6-44 ng/ml; P=0.010), von Willebrand factor (122/91-179% versus 92/66-110%; P=0.001), and soluble intercellular adhesion molecule-1(227/187-291 ng/ml versus 206/185-247 ng/ml; P=0.044) were all higher in non-dippers than in dippers. Adjustment for gender, ethnicity, age, body mass index, smoking status, hypertension status, and social class revealed independent effects of non-dipping. Non-dippers continued to have higher D-dimer (P=0.030) and von Willebrand factor (P=0.034) than dippers. A similar trend not reaching statistical significance emerged for soluble intercellular adhesion molecule-1 (P=0.055). In contrast, dipping status had no effect on interleukin-6.

CONCLUSION

Nocturnal BP non-dipping is associated with elevated levels of molecules related to endothelial dysfunction and atherosclerosis. The finding provides one possible mechanism linking non-dipping with cardiovascular disease.

Adaptation related to cytokines in man: effects of regular swimming in ice-cold water

The cytokine response after thermal stress (sauna + swimming in ice-cold water) was investigated in subjectively healthy persons. Two groups were studied at the end of the winter season: habitual and inexperienced winter swimmers. Blood was collected at rest, after a sauna bath and after a short swim in ice-cold water. Conventional methods and ELISA kits were used to determined the blood picture, serum cortisol and dehydroepiandrosterone sulphate, plasma anti-diuretic hormone (ADH) levels, and the levels of several cytokines in plasma and in the supernatants of blood cell cultures which were stimulated with lipopolysaccharide (LPS). In regular winter swimmers, the concentrations of plasma interleukin 6 (IL-6), leukocytes, and monocytes at rest were significantly higher than in inexperienced subjects. In experienced female winter swimmers, the plasma concentration of the soluble receptor for IL-6 was significantly lower than in inexperienced female swimmers. In both groups, granulocytosis, haemoconcentration and significant increases in the concentrations of ADH, cortisol and IL-6 were observed after the stimuli. However, the changes in the cortisol concentration were dramatically larger in habitual winter swimmers. A significant correlation was found between the delta values of cortisol and the basal concentrations of IL-6. In cell cultures, the LPS-induced release of IL-1beta and IL-6 was higher at rest in the inexperienced winter swimmers. This release was dramatically suppressed after exposure to the stimuli in the inexperienced winter swimmers but tended to increase in the regular winter swimmers. These stresses appear to challenge both the neuro-endocrine and the immune systems and the results indicate that adaptive mechanisms occur in habitual winter swimmers.