The incidence and characteristics of silent cerebral infarction in elderly diabetic patients: association with serum-soluble adhesion molecules

Sex and aging signatures of proteomics in human cerebrospinal fluid identify distinct clusters linked to neurodegeneration

Sex and age are major risk factors for chronic diseases. Recent studies examining age-related molecular changes in plasma provided insights into age-related disease biology. Cerebrospinal fluid (CSF) proteomics can provide additional insights into brain aging and neurodegeneration. By comprehensively examining 7,006 aptamers targeting 6,139 proteins in CSF obtained from 660 healthy individuals aged from 43 to 91 years old, we subsequently identified significant sex and aging effects on 5,097 aptamers in CSF. Many of these effects on CSF proteins had different magnitude or even opposite direction as those on plasma proteins, indicating distinctive CSF-specific signatures. Network analysis of these CSF proteins revealed not only modules associated with healthy aging but also modules showing sex differences. Through subsequent analyses, several modules were highlighted for their proteins implicated in specific diseases. Module 2 and 6 were enriched for many aging diseases including those in the circulatory systems, immune mechanisms, and neurodegeneration. Together, our findings fill a gap of current aging research and provide mechanistic understanding of proteomic changes in CSF during a healthy lifespan and insights for brain aging and diseases.

Diabetic patients with chronic kidney disease: Non-invasive assessment of cardiovascular risk

The prevalence and burden of diabetes mellitus and chronic kidney disease on global health and socioeconomic development is already heavy and still rising. Diabetes mellitus by itself is linked to adverse cardiovascular events, and the presence of concomitant chronic kidney disease further amplifies cardiovascular risk. The culmination of traditional (male gender, smoking, advanced age, obesity, arterial hypertension and dyslipidemia) and non-traditional risk factors (anemia, inflammation, proteinuria, volume overload, mineral metabolism abnormalities, oxidative stress, etc.) contributes to advanced atherosclerosis and increased cardiovascular risk. To decrease the morbidity and mortality of these patients due to cardiovascular causes, timely and efficient cardiovascular risk assessment is of huge importance. Cardiovascular risk assessment can be based on laboratory parameters, imaging techniques, arterial stiffness parameters, ankle-brachial index and 24 h blood pressure measurements. Newer methods include epigenetic markers, soluble adhesion molecules, cytokines and markers of oxidative stress. In this review, the authors present several non-invasive methods of cardiovascular risk assessment in patients with diabetes mellitus and chronic kidney disease.

Serum E-selectin concentration is associated with risk of metabolic syndrome in females

OBJECTIVES

Traits of metabolic syndrome (MetS) and biomarkers of inflammation and endothelial dysfunction were examined. We investigated the differences of various biomarkers among individuals with or without Mets in a gender-specific manner. The gender-specific associations between E-selectin and MetS were further evaluated.

METHODS

A total of 205 patients were recruited from the outpatient clinics of Tri-Service General Hospital, Taipei, Taiwan. Inclusion criteria were age between 20-75 years and BMI < 35 kg/m2. Demographic, anthropometric and MetS index data were compared between genders. Markers of inflammation and endothelial dysfunction were compared between individuals with or without MetS by gender.

RESULTS

Age-adjusted E-selectin values showed significant positive correlations with BMI, waist-hip ratio, fasting plasma glucose, systolic and diastolic blood pressure, triglycerides, TNF-α, hsCRP and ICAM-1, and inverse correlation with HDL cholesterol. E-selectin levels were positively correlated with numbers of MetS components in females (P < 0.001) but not in males (P = 0.125).

CONCLUSIONS

Increased E-selectin levels are significantly associated with increased MetS risk in females, but not in males.

Cerebrospinal fluid biomarkers for Alzheimer's and vascular disease vary by age, gender, and APOE genotype in cognitively normal adults

BACKGROUND

This study sought to evaluate gender and APOE genotype-related differences in the concentrations of cerebrospinal fluid (CSF) biomarkers for Alzheimer's disease (AD) and cerebrovascular injury across the life span of cognitively normal adults.

METHODS

CSF amyloid beta_1-42 (Aβ₄₂), phospho-tau-181 (p-tau₁₈₁), and total tau were measured in 331 participants who were between the ages of 21 and 100. CSF E-selectin and vascular cell adhesion protein 1 (VCAM1) were measured in 249 participants who were between the ages of 50 and 100.

RESULTS

CSF total tau and p-tau₁₈₁ increased with age over the adult life span (p < 0.01) with no gender differences in those increases. CSF Aβ₄₂ concentration varied according to age, gender, and APOE genotype (interaction of age × gender × ε4, p = 0.047). CSF VCAM1, but not E-selectin, increased with age (p < 0.01), but both were elevated in men compared to women (p < 0.01).

CONCLUSIONS

Female APOE-ε4 carriers appear at higher risk for AD after age 50. In contrast, men may experience a relatively higher rate of cerebrovascular injury in middle and early old age.

The Association between Carotid Artery Atherosclerosis and Silent Brain Infarction: A Systematic Review and Meta-analysis

BACKGROUND

Carotid atherosclerosis is responsible for ~20% of ischemic strokes, but it is unclear whether carotid disease is associated with the presence of downstream silent brain infarction (SBI). We performed a systematic review and meta-analysis to study the relationship between SBI and 2 separate manifestations of carotid atherosclerosis, carotid intima-media thickening (IMT) and luminal stenosis.

METHODS

Ovid MEDLINE, Ovid Embase, and the Cochrane Library Database were searched with an additional search of references and citing articles of target studies. Articles were included if they reported an association between carotid IMT or stenosis and magnetic resonance imaging-defined SBI, excluding SBIs found after carotid intervention.

RESULTS

We pooled 7 studies of carotid IMT reporting on 1469 subjects with SBI and 5102 subjects without SBI. Subjects with SBI had a larger mean IMT than subjects without SBI (pooled standardized mean difference, .37; 95% confidence interval [CI], .23-.51; P < .0001). We pooled 11 studies of carotid stenosis reporting on 12,347 subjects (2110 subjects with carotid stenosis and 10,237 subjects without carotid stenosis). We found a higher prevalence of SBI among subjects with carotid stenosis (30.4% versus 17.4%). Our pooled random-effects analysis showed a significant positive relationship between carotid stenosis and SBI (odds ratio, 2.78; 95% CI, 2.19-3.52; P < .0001).

CONCLUSIONS

Two forms of atherosclerotic disease, carotid IMT and stenosis, are both significantly associated with SBI. This review highlights a lack of consistent definitions for carotid disease measures and little evidence evaluating SBI prevalence downstream from carotid stenosis.

Pathogenesis and neuroimaging of cerebral large and small vessel disease in type 2 diabetes: A possible link between cerebral and retinal microvascular abnormalities

Diabetes patients have more than double the risk of ischemic stroke compared with non‐diabetic individuals, and its neuroimaging characteristics have important clinical implications. To understand the pathophysiology of ischemic stroke in diabetes, it is important to focus not only on the stroke subtype, but also on the size and location of the occlusive vessels. Specifically, ischemic stroke in diabetes patients might be attributed to both large and small vessels, and intracranial internal carotid artery disease and small infarcts of the posterior circulation often occur. An additional feature is that asymptomatic lacunar infarctions are often seen in the basal ganglia and brain stem on brain magnetic resonance imaging. In particular, cerebral small vessel disease (SVD), including lacunar infarctions, white matter lesions and cerebral microbleeds, has been shown to be associated not only with stroke incidence, but also with the development and progression of dementia and diabetic microangiopathy. However, the pathogenesis of cerebral SVD is not fully understood. In addition, data on the association between neuroimaging findings of the cerebral SVD and diabetes are limited. Recently, the clinical importance of the link between cerebral SVD and retinal microvascular abnormalities has been a topic of considerable interest. Several clinical studies have shown that retinal microvascular abnormalities are closely related to cerebral SVD, suggesting that retinal microvascular abnormalities might be pathophysiologically linked to ischemic cerebral SVD. We review the literature relating to the pathophysiology and neuroimaging of cerebrovascular disease in diabetes, and discuss the problems based on the concept of cerebral large and small vessel disease.

Increased CSF E-Selectin in Clinical Alzheimer's Disease without Altered CSF Aβ42 and Tau

Clinically diagnosed Alzheimer's disease (AD) is pathologically heterogeneous. In this multicenter cohort of 215 clinically diagnosed AD patients and 249 controls, E-selectin and vascular cell adhesion molecule 1 (VACM-1) were measured along with amyloid-β peptide 1-42 (Aβ42) and tau. We discovered that E-selectin, a biomarker of endothelial function/vascular injury, was inversely correlated with cerebrospinal fluid (CSF) tau/Aβ42 ratio and significantly elevated in clinical AD patients without the typical AD CSF biomarker signature (i.e., low tau/Aβ42 ratio) compared to those with the signature. These findings suggest that E-selectin may be an objective biomarker related to vascular mechanisms contributing to dementia.

Blood and CSF biomarkers in brain subcortical ischemic vascular disease: Involved pathways and clinical applicability

Vascular dementia is the second most common type of dementia after Alzheimer’s disease (AD). Subcortical ischemic vascular disease refers to a form of vascular cognitive impairment characterized by the presence of diffuse white matter hyperintensities (WMHs) and multiple lacunar infarcts. These neuroimaging findings are mainly caused by cerebral small-vessel disease (cSVD) and relate to aging and cognitive impairment, but they can also be silent and highly prevalent in otherwise healthy individuals. We aimed to review studies on blood and cerebrospinal fluid (CSF) markers related to the presence of WMHs and lacunar infarcts that have been conducted in the past in large population-based studies and in high-risk selected patients (such as those with vascular risk factors, vascular cognitive impairment, or AD). Relevant associations with the presence and progression of cSVD have been described in the blood for markers related to inflammatory processes, endothelial damage and coagulation/fibrinolysis processes, etc. Also, different combinations of CSF markers might help to differentiate between etiologic types of dementia. In the future, to translate these findings into clinical practice and use biomarkers to early diagnosis and monitoring vascular cognitive impairment would require the replication of candidate markers in large-scale, multicenter, and prospectively designed studies.

Cognitive impairment in diabetic patients: Can diabetic control prevent cognitive decline?

It is well recognized that the prevalence of dementia is higher in diabetic patients than non‐diabetic subjects. The incidence of diabetes has been increasing because of dramatic changes in lifestyles, and combined with longer lifespans as a result of advances in medical technology, this has brought about an increase in the number of elderly diabetic patients. Together, aging and diabetes have contributed to dementia becoming a serious problem. Progression to dementia reduces quality of life, and imposes a burden on both patients themselves and the families supporting them. Therefore, preventing the complication of dementia will become more and more important in the future. Although many mechanisms have been considered for an association between diabetes and cognitive dysfunction, glucose metabolism abnormalities such as hyperglycemia and hypoglycemia, and insulin action abnormalities such as insulin deficiency and insulin resistance can be causes of cognitive impairment. Recent large‐scale longitudinal studies have found an association between glycemic control and cognitive decline, although it is still unclear how cognitive decline might be prevented by good glycemic control. However, at an early stage, it is necessary to detect moderate cognitive dysfunction and try to reduce the risk factors for it, which should result in prevention of dementia, as well as vascular events. In the present review, in addition to outlining an association between diabetes and cognitive function, we discuss how glycemic control and cognitive decline are related.

Role of cell adhesion molecules in acute ischemic stroke

BACKGROUND AND OBJECTIVES

The expression of soluble adhesion molecules inter-cellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), besides activation of endothelial cells and transendothelial migration of leukocytes, play an important role in inflammation and progression of ischemic injury after acute stroke. The aim of this study was to determine serum levels of soluble ICAM-1 and VCAM-1 in patients with acute ischemic stroke and controls and correlate them according to etiological subtypes (thromboembolic or lacunar stroke), stroke severity and disability after acute stroke.

PATIENTS AND METHODS

Hospital-based prospective study of acute stroke patients hospitalized between December 2008 and September 2009 at the University Hospital Sestre Milosrdnice in Zagreb, Croatia.

METHODS

We enrolled 110 patients with acute ischemic stroke and 93 healthy individuals as controls. Serum concentrations of VCAM-1 and ICAM-1 were determined by means of quantitative sandwich enzyme immunoassay. Patients were classified according to etiological subtype, clinical severity of stroke and disability after stroke.

RESULTS

There was no significant difference between levels of soluble adhesion molecules VCAM-1 and ICAM-1 in patients and in controls. Levels of VCAM-1 were significantly higher in patients with thromboembolic stroke than in controls. There was no significant correlation between levels of soluble adhesion molecules VCAM-1 and ICAM-1 and stroke severity and disability. There was marked biological interindividual variability in all patient groups.

CONCLUSION

This study confirms the role of adhesion molecule VCAM-1 in the pathogenesis of acute thromboembolic stroke.

Plasma level of sICAM-1 is associated with the extent of white matter lesion among asymptomatic elderly subjects

OBJECTIVE

Inflammatory endothelial activation mediated by intercellular adhesion molecule-1 (ICAM-1) plays a role in the pathogenesis of large- and small-vessel disease. We explored the association between soluble ICAM-1 (sICAM-1) and white matter lesion (WML) as a manifestation of cerebral small-vessel disease.

METHODS

One hundred and seventy-five elderly individuals aged >or= 60 without neurological deficits were studied. Subcortical deep white matter hyperintensity (SDWMH) and periventricular hyperintensity (PVH) were rated separately. Lesions in each category were then divided into three groups (grade 0-I, grade II, grade III) according to the Fazekas scale.

RESULTS

Plasma sICAM-1 levels were positively associated with grades of WML (for SDWMH: 297.4+/-135.6ng/mL in grade 0-I, 391.3+/-145.5ng/mL in grade II, and 450.2+/-232.9ng/mL in grade III, p<0.001; for PVH: 282.5+/-116.5ng/mL in grade 0-I, 402.3+/-160.4ng/mL in grade II, and 428.1+/-227.7ng/mL in grade III, p<0.001). Multivariate analysis showed higher sICAM-1 levels, age and hypertension were the independent risk factors associated with the presence and severity of WML. More than 4-fold increased risk of WML was observed in patients with the highest quartile of sICAM-1 (all WML OR=4.694, 95% CI: 1.805-12.204; moderate WML OR=4.618, 95% CI: 1.543-13.825; severe WML OR=4.893, 95% CI: 1.236-19.368).

CONCLUSION

Increased plasma sICAM-1 suggests inflammatory process may be involved in the pathogenesis of WML.

Association between future events of brain infarction and soluble levels of intercellular adhesion molecule-1 and C-reactive protein in patients with type 2 diabetes mellitus

We investigated the influence of the reciprocal association between serum levels of high-sensitivity C-reactive protein (hs-CRP) and intercellular adhesion molecule-1 (sICAM-1) on the risk of brain infarction in type 2 diabetic patients. One hundred seventy nine middle-aged and elderly diabetic patients without histories of cardiovascular events were followed up for an average of 8 years. Fourteen patients developed symptomatic brain infarction (BI) during follow-up. These patients had significantly higher blood pressure, longer duration of diabetes, silent brain infarction, microvascular complications such as macroalbuminuria, and higher creatinine, sICAM-1 and hs-CRP levels at baseline as compared with those without BI. A high risk of stroke was observed in patients with high levels of sICAM-1 (>260microg/L) and hs-CRP (>0.83mg/L) at baseline, respectively, and patients with high levels of both were more likely to develop BI. In addition, sICAM-1 levels were significantly correlated with systolic blood pressure and glycemic control index, whereas hs-CRP levels were correlated with fasting insulin levels, HDL-cholesterol, triglycerides, and uric acid. Consequently, sICAM-1 and hs-CRP levels were, respectively, reflected in different cardiovascular risk factors. This study suggests that both measurements of hs-CRP and sICAM-1 levels are useful as a predictor of future stroke in diabetic subjects.

Early treatment-related changes in diabetes and cardiovascular disease risk markers in first episode psychosis subjects

OBJECTIVE

To examine prospective changes in cardiovascular disease (CVD) and type-2 diabetes risk factors in young adult first episode psychotic (FEP) patients treated with second generation antipsychotic medications.

METHODS

At baseline, fasting serum and anthropometric measures were obtained from 45 FEP patients and 41 healthy adults (controls) of similar age, ethnicity and sex; sixteen of the FEP patients remained on the same antipsychotic medication and were available for a second blood draw at 24 weeks of treatment. Serum was assayed for glucose, insulin, triglycerides, total cholesterol and high and low density lipoproteins (HDL, LDL), adiponectin, leptin, interleukin 6, E-selectin and VCAM-1. Wilcoxon nonparametric tests were used to compare risk markers between the FEP and control group at baseline and to evaluate pre-post treatment changes within the FEP group.

RESULTS

At baseline, the distributions of risk marker values were similar between the two groups and the percentages of FEP patients and healthy controls who were overweight/obese, dyslipidemic, hyperglycemic, and hyperinsulinemic did not differ. At 24 weeks, compared to baseline, FEP patients showed significant increases in BMI (p=0.0002), glucose (p=0.0449), insulin (p=0.0161), cholesterol (p=0.0129), leptin (p=0.0215), and E-selectin (p=0.0195), and a decrease in adiponectin (p=0.0371).

CONCLUSIONS

Among patients with first episode psychosis, 6-month treatment with second generation antipsychotics is associated with the exacerbation of pre-existing and emergence of new CVD and diabetes risk factors.

Carotid intima-media thickness and markers of inflammation, endothelial damage and hemostasis

BACKGROUND

Different soluble molecules involved in inflammation, endothelial damage, or hemostasis are recognized as potential cardiovascular risk markers. Studies to assess the role of these markers in the atherosclerotic process by evaluating their relationship to carotid intima-media thickness (C-IMT) tend to provide contrasting results.

PURPOSE

To perform a review of studies addressing the association between C-IMT and soluble markers and to investigate whether the observed inconsistencies could be explained by the characteristics of the patients included in different studies, for example prevalence of atherosclerotic disease (atherosclerotic burden), gender, age, or occurrence of specific vascular risk factors (VRFs).

DATA SOURCES

PubMed and Embase (January 1990 to March 2006).

STUDY SELECTION

Articles in English reporting original cross-sectional studies.

DATA EXTRACTION

Two authors independently extracted data on study design, population, sample size, ultrasonic methodology, and statistical approach.

DATA SYNTHESIS

Despite the marked heterogeneity of results presented in the literature, meta-analysis established that studies showing positive associations between C-IMT and plasma levels of C-reactive protein (CRP) or fibrinogen are in the majority. Funnel plot analyses suggested the absence of an important publication bias. Data on the relationships between C-IMT and other soluble markers are by contrast scanty, contradictory, or unconfirmed by multivariate (as opposed to univariate) analyses, and the freedom from publication bias here cannot be vouched for. The degree of atherosclerotic burden in the population studied does not account for the heterogeneity of findings reported. Gender, noninsulin-dependent diabetes mellitus (NIDDM) and hypercholesterolemia influence the association between C-IMT and CRP. Blood pressure and hypercholesterolemia influence the association between C-IMT and fibrinogen. For all the other soluble markers considered, the number of groups was too small for this kind of statistical considerations.

LIMITATIONS

Heterogeneity in ultrasound methodologies and in statistical approach limited comparability between studies. For most soluble markers, publication bias of positive results cannot be excluded.

CONCLUSIONS

Only CRP and fibrinogen seem to be unequivocally related to C-IMT. For all the other soluble markers considered, no clear-cut conclusions can be drawn.

Cardiovascular disease in diabetic nephropathy patients: cell adhesion molecules as potential markers?

Cardiovascular disease is a major complication of diabetes mellitus, especially for patients with diabetic nephropathy. The underlying factor or pathogenic mechanism that links diabetic nephropathy with cardiovascular disease is not known. The endothelial cell adhesion molecules, intercellular adhesion molecule-1 or vascular cell adhesion molecule-1, play a crucial role in the initiation of atherosclerosis. Levels of both cell adhesion molecules are raised by the diabetic and kidney disease states. This review focuses on these important cell adhesion molecules and their role in the pathogenesis of cardiovascular disease in diabetes and diabetic nephropathy.

Soluble adhesion molecules and C-reactive protein in the progression of silent cerebral infarction in patients with type 2 diabetes mellitus

The purpose of this study was to investigate the association between the progression of silent cerebral infarction (SCI) and levels of soluble adhesion molecules and high-sensitivity C-reactive protein (hs-CRP) in type 2 diabetic patients. One hundred twenty middle-aged and elderly diabetic patients without histories of vascular events were followed up for a period of 3 years. We measured levels of soluble intercellular adhesion molecule 1 (sICAM-1), vascular cell adhesion molecule 1, E-selectin, and hs-CRP and assessed brain ischemic lesions by magnetic resonance imaging at baseline and 3 years later. Silent cerebral infarction was observed in 13% of the patients at baseline, and these patients were significantly older and had significantly higher blood pressure than those without SCI. Thirty-two patients had newly diagnosed SCI after 3 years. There were no significant differences in factors such as age, blood pressure, and diabetic control between patients without SCI and those in whom it was newly diagnosed. However, only sICAM-1 levels, but not the other soluble adhesion molecules or hs-CRP, were associated with the progression of SCI, and this relationship remains after adjustment for risk factors. On the other hand, higher levels of sICAM-1 and hs-CRP at baseline were observed in 7 patients who were excluded from the present study because of the onset of symptomatic cerebral infarction during follow-up. Our present study suggests that sICAM-1 levels may be a potential marker for SCI, which may lead to future stroke and vascular dementia, and that this marker could be useful in monitoring disease progression and as a surrogate marker in treatment studies.

Relations of Serum High-Sensitivity C-Reactive Protein and Interleukin-6 Levels With Silent Brain Infarction

BACKGROUND AND PURPOSE

Small silent brain infarction (SBI) is often found on magnetic resonance (MR) images of apparently healthy individuals at cardiovascular risk. Particularly, small SBI found in subcortical white matter, basal ganglia, or thalamus is thought to be caused by cerebral small vessel disease. Although several lines of evidence suggest a role of inflammatory processes in atherothrombotic vascular events, their involvement in SBI remains to be determined. This study examines the associations between serum inflammatory markers and SBI as a manifestation of cerebral small vessel disease.

METHODS

One hundred ninety-four patients without histories of cardiovascular accidents were prospectively enrolled for this study. All patients underwent brain MR imaging and carotid ultrasonography, and patients with SBI diagnosed underwent further MR angiography. As common inflammatory markers, serum levels of high-sensitivity C-reactive protein (hsCRP) and interleukin-6 (IL-6) were evaluated.

RESULTS

SBIs were found in 40 patients, and all of those were located in subcortical and infratentorial area, without MR angiographic evidence for obstructive lesions in proximal cerebral arteries. Mean hsCRP and IL-6 levels were higher in patients with SBI than in those without. Also, higher levels of both hsCRP (odds ratio [OR], 1.85 per standard deviation [SD] increase) and IL-6 (OR, 2.00/SD increase) were associated with higher likelihood for SBI. Moreover, the associations were only slightly attenuated when adjusting traditional cardiovascular risk factors and carotid IMT.

CONCLUSIONS

Higher levels of hsCRP and IL-6 appear to be associated with small SBI, suggesting a role of inflammatory processes in cerebral small vessel disease.

Effect of postprandial hypertriglyceridemia and hyperglycemia on circulating adhesion molecules and oxidative stress generation and the possible role of simvastatin treatment

Adhesion molecules, particularly intracellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1, and E-selectin, have been associated with cardiovascular disease. Elevated levels of these molecules have been reported in diabetic patients. Postprandial hypertriglyceridemia and hyperglycemia are considered risk factors for cardiovascular disease, and evidence suggests that postprandial hypertriglyceridemia and hyperglycemia may induce an increase in circulating adhesion molecules. However, the distinct role of these two factors is a matter of debate. Thirty type 2 diabetic patients and 20 normal subjects ate three different meals: a high-fat meal, 75 g of glucose alone, and a high-fat meal plus glucose. Glycemia, triglyceridemia, plasma nitrotyrosine, ICAM-1, VCAM-1, and E-selectin were assayed during the tests. Subsequently, diabetic subjects took simvastatin 40 mg/day or placebo for 12 weeks. The three tests were performed again at baseline, between 3 and 6 days after starting the study, and at the end of each study. High-fat load and glucose alone produced an increase of nitrotyrosine, ICAM-1, VCAM-1, and E-selectin plasma levels in normal and diabetic subjects. These effects were more pronounced when high fat and glucose were combined. Short-term simvastatin treatment had no effect on lipid parameters, but reduced the effect on adhesion molecules and nitrotyrosine, which was observed during every different test. Long-term simvastatin treatment was accompanied by a lower increase in postprandial triglycerides, which was followed by smaller variations in ICAM-1, VCAM-1, E-selectin, and nitrotyrosine during the tests. This study shows an independent and cumulative effect of postprandial hypertriglyceridemia and hyperglycemia on ICAM-1, VCAM-1, and E-selectin plasma levels, suggesting oxidative stress as a common mediator of such effects. Simvastatin shows a beneficial effect on oxidative stress and the plasma levels of adhesion molecules, which may be ascribed to a direct effect in addition to the lipid-lowering action of the drug.

Inflammation and infections as risk factors for ischemic stroke

BACKGROUND

Inflammatory processes have fundamental roles in stroke in both the etiology of ischemic cerebrovascular disease and the pathophysiology of cerebral ischemia. We summarize clinical data on infection and inflammation as risk or trigger factors for human stroke and investigate current evidence for the hypothesis of a functional interrelation between traditional risk factors, genetic predisposition, and infection/inflammation in stroke pathogenesis.

SUMMARY OF REVIEW

Several traditional vascular risk factors are associated with proinflammatory alterations, including leukocyte activation, and predispose cerebral vasculature to thrombogenesis on inflammatory stimulation. Furthermore, accumulation of inflammatory cells, mainly monocytes/macrophages, within the vascular wall starts early during atherogenesis. During later disease stages, their activation can lead to plaque rupture and thrombus formation, increasing stroke risk. Inflammatory markers (eg, leukocytes, fibrinogen, C-reactive protein) are independent predictors of ischemic stroke. Chronic infections (eg, infection with Chlamydia pneumoniae or Helicobacter pylori) were found to increase the risk of stroke; however, study results are at variance, residual confounding is not excluded, and causality is not established at present. In case-control studies, acute infection within the preceding week was a trigger factor for ischemic stroke. Acute and exacerbating chronic infection may act by activating coagulation and chronic infections and may contribute to atherogenesis. Genetic predisposition of the inflammatory host response may be an important codeterminant for atherogenesis and stroke risk.

CONCLUSIONS

Inflammation contributes to stroke risk via various interrelated mechanisms. Infectious diseases, traditional risk factors, and genetic susceptibility may cooperate in stimulating inflammatory pathways. Final proof of a causal role of infectious/inflammatory mechanisms in stroke pathogenesis is still lacking and will require interventional studies.

Inflammatory cell adhesion molecules in ischemic cerebrovascular disease

BACKGROUND

In this review we discuss the role of inflammatory cell adhesion molecules (CAMs) in ischemic stroke and in delayed cerebral ischemia after subarachnoid hemorrhage. Vascular endothelial cells and leukocytes express several inflammatory adhesion receptors, the most important of which are the selectins, immunoglobulin gene superfamily CAMs, and beta2 integrins. They mediate the transmigration process of leukocytes to the abluminal side of the endothelium.

SUMMARY OF REVIEW

There is ample evidence from animal models of middle cerebral artery occlusion that expression of CAMs is associated with cerebral infarct size. Absence of CAMs in knockout animals resulted in reduced infarct size. When middle cerebral artery occlusion in experimental stroke was followed by reperfusion, administration of anti-CAM antibodies decreased infarct size. Thus far, anti-CAM treatment has not been successful in patients with ischemic stroke. Inflammatory CAM may also play a role in the pathogenesis of delayed cerebral ischemia after subarachnoid hemorrhage. In animal models, increased expression of CAMs has been observed in vasospastic arteries. Increased concentrations of CAMs have also been found in cerebrospinal fluid of patients with subarachnoid hemorrhage.

CONCLUSIONS

Further research on the role of inflammatory CAMs in the pathogenesis of ischemic cerebrovascular disorders should lead to new diagnostic and therapeutic strategies.

Effects of severe, uncontrolled hypertension on endothelial activation: soluble vascular cell adhesion molecule-1, soluble intercellular adhesion molecule-1 and von Willebrand factor

OBJECTIVES

The molecular mechanisms whereby severe, uncontrolled hypertension (SHT) is translated into acute vascular target organ dysfunction have not been completely defined. We sought to determine whether SHT is associated with pressure-dependent endothelial activation as assessed by soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1) and von Willebrand Factor (vWF).

METHODS

We determined sVCAM-1, sICAM-1 and vWF in three groups: (i) untreated patients referred specifically for treatment of SHT [diastolic blood pressure (DBP) > or = 120 mm Hg; n = 24]; (ii) untreated patients with established mild hypertension (MHT; DBP 95-100 mmHg; n = 19); and (iii) normotensive volunteers (DBP < or = 90; n = 16).

RESULTS

By analysis of variance, sVCAM-1 (P = 0.002), sICAM-1 (P = 0.02) and vWF (P = 0.009) were greater in SHT and MHT than in normotensives but did not differ between SHT and MHT. We observed a significant positive correlation between blood pressure and soluble activation markers at lower blood pressures (normotensives and MHT considered together) that was not present in SHT.

CONCLUSIONS

Even mild elevation of blood pressure may be sufficient to activate the expression of adhesion molecules. Mechanisms other than the endothelial expression of adhesion molecules may be important in mediating the accelerated target organ injury produced by SHT in humans. Concentrations of soluble adhesion molecules and vWF may depend more strongly upon factors in the hypertensive microenvironment other than the absolute level of blood pressure.

Genotype-specific association between circulating soluble cellular adhesion molecules and carotid intima-media thickness in community residents: J-SHIPP study. Shimanami Health Promoting Program

Plasma levels of soluble forms of cellular adhesion molecules (CAMs) and their relationships with carotid intima-media thickness (IMT) were investigated in community residents. Plasma levels of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) were measured by ELISA in 200 community residents in Japan. Carotid IMT showed a weak but significant positive correlation with the plasma levels of both sICAM-1 (r=0.175, p=0.013) and sVCAM-1 (r=0.19, p=0.0075). Gene polymorphisms of angiotensin converting enzyme (ACE) insertion/deletion (I/D), angiotensinogen (AGT) M235T, angiotensin II type 1 receptor (AT1R) A1166C and apolipoprotein E (apoE) were determined for each subject. The plasma level of sVCAM-1 tended to be lower in subjects with the ACE DD genotype than in those with the ACE ID and II genotypes (373+/-94, 421+/-133, 443+/-135 ng/ml, respectively, p=0.056). However, there were no genotype-specific differences in the plasma levels of soluble forms of CAMs for the other genes examined. In a separate analysis, the plasma level of sICAM-1 was significantly associated with carotid IMT in ACE D carriers (ID + DD) (r=0.28, p=0.002), AGT M carriers (MT + MM) (r=0.32, p=0.0045), and subjects with apoE4 (r=0.35, p=0.036). In contrast, the plasma level of sVCAM-1 showed significant positive correlations with carotid IMT in subjects with the ACE II genotype (r=0.33, p=0.0027) or AGT TT genotype (r= 0.22, p=0.015), and subjects with apoE E2/E3 or E3/E3 (r=0.16, p=0.043). Stepwise regression analysis showed that plasma sVCAM-1 was independently associated with carotid IMT in subjects with the ACE II genotype or apoE4 genotype. Similarly, the plasma level of sICAM-1 was independently associated with carotid IMT in AGT M carriers. These findings suggest that genetic background could be involved in the association between plasma CAMs and atherosclerosis.

The effect of cigarette smoking on soluble adhesion molecules in middle-aged patients with Type 2 diabetes mellitus

AIMS

To investigate the effect of smoking on soluble adhesion molecules in middle-aged diabetic patients.

METHODS

One hundred out-patients with Type 2 diabetes and 100 age- and sex-matched non-diabetic subjects without clinical macrovascular disease were selected. Soluble serum levels of adhesion molecules were analysed using enzyme immunoassay. Carotid atherosclerosis was assessed using an ultrasound system.

RESULTS

When compared with non-diabetic subjects, soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1), and sE-selectin were found at significantly high levels in diabetic patients and significantly higher levels of sICAM-1, sE-selectin, and sP-selectin were observed in current smokers than never-smokers among diabetic or non-diabetic subjects, respectively. The combined, but not enhanced, effects of diabetes mellitus and smoking were observed in sICAM-1 and sE-selectin levels. Additionally, levels of sICAM-1 (P < 0.05) and sE-selectin (P < 0.01), but not sP-selectin, were high in ex-smokers when compared with never-smokers among diabetic patients. Diabetic smokers were also found to have marked carotid atherosclerosis, which was related to increased levels of sICAM-1.

CONCLUSIONS

Our present study shows that levels of adhesion molecules were higher in diabetic smokers than diabetic non-smokers or non-diabetic smokers, and that cessation after chronic smoking did not restore the levels of sICAM-1 and sE-selectin, though sP-selectin levels were restored. These data suggest a possible mechanism for accelerated atherosclerosis induced by smoking in patients with diabetes.

Effects of nasal continuous positive airway pressure on soluble cell adhesion molecules in patients with obstructive sleep apnea syndrome

PURPOSE

Obstructive sleep apnea syndrome is common in middle-aged men and may be associated with an increased risk of cardiovascular disease. We investigated the effect of nasal continuous positive airway pressure (CPAP) treatment on levels of soluble cell adhesion molecules-which have been shown to be associated with the development of atherosclerosis-in these patients.

SUBJECTS AND METHODS

We studied 23 patients with obstructive sleep apnea syndrome diagnosed by polysomnography who were treated with nasal CPAP. Serum soluble intercellular adhesion molecule-1, E-selectin, and vascular cell adhesion molecule-1 levels were measured before nasal CPAP was started, and after 3 or 4 days (n = 19), 1 month (n = 23), or 6 months (n = 11) of treatment.

RESULTS

After 3 to 4 days of nasal CPAP therapy, the mean (+/- SD) soluble E-selectin level had decreased from 89 +/- 44 ng/mL to 69 +/- 28 ng/mL (P = 0.002). After 1 month, the soluble intercellular adhesion molecule-1 level had decreased from 311 +/- 116 ng/mL to 249 +/- 74 ng/mL (P = 0.02). After 6 months, soluble vascular cell adhesion molecule-1 levels had not changed significantly, while the mean soluble intercellular adhesion molecule-1 level (212 +/- 59 ng/mL) had decreased further (P = 0.02). Before treatment, soluble intercellular adhesion molecule-1 levels and the apnea and hypopnea index were correlated (r = 0.43, P = 0.04).

CONCLUSIONS

Obstructive sleep apnea and hypopnea have a significant adverse effect on serum soluble cell adhesion molecule-1 levels that may be reduced by nasal CPAP treatment.

Cardiovascular disease in diabetes mellitus type 2: a potential role for novel cardiovascular risk factors

A major consequence of diabetes mellitus type 2 is the accelerated development of atherosclerosis. Assessment of conventional risk factors such as plasma lipids, lipoproteins and hypertension only partly account for the excessive risk of developing cardiovascular disease in this population. Increasing evidence has emerged suggesting that conditions associated with diabetes mellitus type 2, such as insulin resistance, hyperinsulinemia and hyperglycemia, may also play a significant role in regulating 'novel' cardiovascular risk factors. These factors and their potential roles in the development of atherosclerosis and cardiovascular events are discussed in this review.

Circulating intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin in patients with type 2 diabetes mellitus

Serum levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin in patients with type 2 diabetes mellitus (n = 64) and control subjects (n = 40) were studied. Serum ICAM-1 concentrations in diabetic patients were significantly higher than those of control subjects (378.2 +/- 70.0 versus 220.4 +/- 31.8 ng/ml, P < 0.01). By multiple regression analysis, hemoglobin A1c was independently associated with serum ICAM-1 concentration in patients with diabetes. The serum VCAM-1 concentration of diabetic patients with macroangiopathy was higher than those of patients without macroangiopathy and of control subjects (806.9 + 276.5 versus 639.0 +/- 146.0 (P < 0.01), and 652.1 +/- 146.9 ng/ml (P < 0.01), respectively). There was no difference in serum E-selectin concentration between diabetic patients with or without macroangiopathy and normal control subjects. These results suggest that adhesion molecules may contribute to the development of atherosclerosis in the diabetic state.

Decreased plasma endothelin-1 levels in asymptomatic type I diabetic patients with regional cerebral hypoperfusion assessed by Spect

The prevalence of stroke is increased in diabetic patients. The vasoconstrictor peptide endothelin-1 (ET-1) has been implicated in the development of cerebral vasospasm after stroke but its role in the physiological regulation of cerebral blood flow (CBF) is not well known. Our aim was to assess the relationship between CBF and plasma ET-1 levels in type I diabetic patients. Regional CBF was assessed semi-quantitatively by 99Tc(m)-hexamethylpropylene-amine-oxime (99Tc(m)-HMPAO) single photon emission computed tomography (SPECT) in 50 cerebral "regions of interest" (ROIs) of 19 type I diabetic patients without clinical evidence of cerebral disease, and 10 healthy control subjects. In both groups, plasma ET-1 levels were measured. Results showed that type I diabetic patients had significantly more hypoperfusion ROIs than control subjects. While up to 68.4% of the type I diabetic patients showed 3 or more hypoperfusion ROIs, only 10% of the control subjects did. Plasma ET-1 levels were lower in the type I diabetes subgroup with 3 or more hypoperfusion ROIs than in the type I diabetes subgroup with less than 3 hypoperfusion ROIs and in the control group. Moreover, an inverse correlation between the number of hypoperfusion ROIs and plasma ET-1 levels (r = 0.47, p = 0.04) was found in the type I diabetes group. It is concluded that plasma ET-1 is decreased in type I diabetic patients with subclinical abnormalities of regional CBF assessed by cerebral SPECT. This fact may reflect a compensatory response to the reduction of the brain perfusion in order to prevent ischemic events in these patients.

Preanalytical Factors (Biological Variation) and the Measurement of Serum Soluble Intercellular Adhesion Molecule-1 in Humans: Influence of the Time of Day, Food Intake, and Physical and Psychological Stress

Background: Adhesion proteins such as soluble intercellular adhesion molecule-1 (sICAM-1) may be important markers for early atherosclerosis and some other diseases. To devise optimum specimen collection procedures, we investigated the effects on serum sICAM-1 of several preanalytical factors (factors that occur before a specimen is analyzed) such as the time of the day, food ingestion, and physical and psychological stress.

Methods: Three sets of experiments were conducted: (a) 30 subjects were investigated during the morning, after an overnight fast, and then after the usual breakfast and at 1200; (b) 20 subjects were studied before and after exposure to thermal stress (sauna + swimming in ice-cold water); and (c) 15 volunteers were investigated after their driving license examination and during a (stress-free) control session. Conventional methods and kits were used to determine the blood picture and serum sICAM-1.

Results: All of these preanalytical factors induced a significant increase (∼10%) in the concentration of sICAM-1.

Conclusion: It is advisable to consider timing, food intake, and stress when collecting specimens and analyzing data on the concentration of sICAM-1 in serum.