Soluble cell adhesion molecules in hypertensive concentric left ventricular hypertrophy

OBJECTIVE : Concentric left ventricular (LV) hypertrophy is an important cardiovascular risk factor. We investigated whether concentric LV hypertrophy is associated with activation of the vascular endothelium, as assessed by measurements of soluble cell adhesion molecules. DESIGN : E-selectin, intercellular adhesion molecule-1 (ICAM-1), and vascular adhesion molecule-1 (VCAM-1) were measured in serum from hypertensive patients with LV hypertrophy (64 with concentric and 47 with eccentric hypertrophy) and from two matched control groups consisting of 38 hypertensive patients without LV hypertrophy and 38 normotensive subjects. Carotid artery intima-media thickness (IMT) was examined by ultrasonography and LV mass by echocardiography. Neurohormone activities of the renin-angiotensin-aldosterone system were also measured. RESULTS : E-selectin levels were higher in hypertensive than in normotensive subjects (56 +/- 19 versus 49 +/- 11 ng/ml, P = 0.031). Patients with concentric LV hypertrophy had higher levels of E-selectin (61 +/- 21 versus 49 +/- 15 ng/ml, P < 0.001), ICAM-1 (273 +/- 49 versus 254 +/- 49 ng/ml, P = 0.043), VCAM-1 (591 +/- 131 versus 544 +/- 78 ng/ml, P = 0.038) and greater carotid artery IMT (0.99 +/- 0.26 versus 0.83 +/- 0.15 mm, P = 0.018) than eccentric LV hypertrophy patients. E-selectin and VCAM-1 correlated positively to LV relative wall thickness (P = 0.040 and 0.037, respectively), with a similar trend for ICAM-1 (P = 0.083). E-selectin correlated with serum aldosterone (P < 0.001), and E-selectin and ICAM-1 with plasma angiotensin converting enzyme activity (P = 0.003 and 0.036, respectively). CONCLUSION : Increased levels of soluble cell adhesion molecules and an increased carotid artery IMT characterize concentric LV hypertrophy. This indicates perturbations at the vascular level, involving activation of the vascular endothelium in hypertensive patients with concentric LV hypertrophy.     

Should we consider gestational diabetes a vascular risk factor?

Few and contrasting data have reported vascular endothelial dysfunction and increased serum levels of endothelial dysfunction and inflammatory markers in women with previous gestational diabetes mellitus (pGDM). We aimed at evaluating 6.5 years after delivery: intimal medial thickness (IMT), and C-reactive protein (CRP), interleukin-6 (IL-6), E-selectin, intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1) levels in 82 non-pregnant pGDM and 113 control women without pGDM. A subgroup of 21 women, taken from the pGDM group, showing current normal BMI, and no metabolic abnormalities, was separately analysed. All the subjects were free of medication and non-smokers. Women with pGDM, independently by their current BMI and presence of metabolic abnormalities, showed significantly higher E-selectin, ICAM-1 and IMT values than controls. IMT proved to be significantly associated with pGDM in a regression model, after adjustments for BMI, waist circumference, blood pressure, and glucose values (beta=0.046; 95% CI 0.028-0.064). In all pGDM women, E-selectin, ICAM-1, IL-6 and hs-CRP values were significantly associated with IMT in the same model. Post-GDM women, despite being currently free from metabolic abnormalities, showed higher values of markers of endothelial dysfunction and IMT than controls, consistent with an increased future cardiovascular risk.     

Vasculitis and expression of vascular cell adhesion molecule-1, intercellular adhesion molecule-1, and E-selectin in salivary glands of patients with Sjögren's syndrome

OBJECTIVE: We investigated the relationship between clinical symptoms and the grade of histopathological damage and expression of adhesion molecules in salivary glands of patients with Sj?gren's syndrome (SS). METHODS: We studied untreated and recently diagnosed patients with primary (n =20) and secondary SS [10 with SS and rheumatoid arthritis (RA); 10 with SS and systemic lupus erythematosus (SLE)] and 3 healthy controls. Salivary gland biopsies were performed in patients and controls and clinical data were obtained. Salivary gland biopsies were assessed for lymphocyte focus score and expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin. In serum, antinuclear antibodies, rheumatoid factor, anti-Ro and anti-La antibodies, anti-alpha-fodrin IgA and IgG antibodies, and gamma-globulin concentrations were measured. RESULTS: In salivary gland samples, ICAM-1 was expressed on vascular endothelial cells and lymphocyte foci, while VCAM-1 was expressed on vascular endothelial cells and follicular dendritic reticulin cells. There was a positive correlation between lymphocyte focus score and ICAM-1 expression (p < 0.05). We detected correlation between expression of ICAM-1 and VCAM-1, and the expression of VCAM-1 was significantly related to vasculitis (p < 0.05). The areas of E-selectin expression and the dispersion and severity of staining were not correlated with the focus score or with patients' clinical features (p > 0.05). There was no correlation between the staining and autoantibody positivity and gamma-globulin levels. CONCLUSION: ICAM-1 may be important for lymphocyte recruitment and glandular damage and VCAM-1 may be important for the development of vasculitis in patients with SS.     

Novel modulator for endothelial adhesion molecules: adipocyte-derived plasma protein adiponectin

BACKGROUND: Among the many adipocyte-derived endocrine factors, we recently found an adipocyte-specific secretory protein, adiponectin, which was decreased in obesity. Although obesity is associated with increased cardiovascular mortality and morbidity, the molecular basis for the link between obesity and vascular disease has not been fully clarified. The present study investigated whether adiponectin could modulate endothelial function and relate to coronary disease. METHODS AND RESULTS: For the in vitro study, human aortic endothelial cells (HAECs) were preincubated for 18 hours with the indicated amount of adiponectin, then exposed to tumor necrosis factor-alpha (TNF-alpha) (10 U/mL) or vehicle for the times indicated. The adhesion of human monocytic cell line THP-1 cells to HAECs was determined by adhesion assay. The surface expression of vascular cell adhesion molecule-1 (VCAM-1), endothelial-leukocyte adhesion molecule-1 (E-selectin), and intracellular adhesion molecule-1 (ICAM-1) was measured by cell ELISA. Physiological concentrations of adiponectin dose-dependently inhibited TNF-alpha-induced THP-1 adhesion and expression of VCAM-1, E-selectin, and ICAM-1 on HAECs. For the in vivo study, the concentrations of adiponectin in human plasma were determined by a sandwich ELISA system that we recently developed. Plasma adiponectin concentrations were significantly lower in patients with coronary artery disease than those in age- and body mass index-adjusted control subjects. CONCLUSIONS: These observations suggest that adiponectin modulates endothelial inflammatory response and that the measurement of plasma adiponectin levels may be helpful in assessment of CAD risk.     

Soluble intercelluar adhesion molecule-1, E-selectin, vascular cell adhesion molecule-1 and von Willebrand factor in stroke.

We investigated the role of endothelial cell and leukocyte adhesion in the pathophysiology of acute stroke. The immunocytochemical expression of adhesion molecules in brain tissue from six patients who died following acute ischaemic stroke showed weak endothelial expression of intercellular adhesion molecule-1 (ICAM-1), but intense expression of vascular cell adhesion molecule-1 (VCAM-1) by astrocytes and endothelial cells from the infarcted, but not the non-infarcted areas. We also measured soluble adhesion molecules E-selectin, ICAM-1, VCAM-1 and von Willebrand factor (all by enzyme-linked immunosorbent assay) in 21 patients after an acute ischaemic stroke (ictus < 12 h), and again 3 months later. Blood levels in the stroke patients were compared with 82 healthy controls and 22 subjects with carotid atherosclerosis. Compared with healthy controls, both patient groups had raised levels of von Willebrand factor (P < 0.02) but the level of soluble VCAM-1 was raised only in patients with acute stroke (P < 0.02). Levels of von Willebrand factor and soluble VCAM-1 in the stroke patients were still high at 3 months follow-up. We suggest that there might be changes in adhesion molecule expression and release in the acute and chronic stages of ischaemic stroke, where blood levels are related to immunocytochemical findings on infarcted brain. These changes may perhaps be part of the complex pathophysiological responses to infarction and repair of brain tissue following stroke.     

Soluble VCAM-1 and E-selectin, but not ICAM-1 discriminate endothelial injury in patients with documented coronary artery disease

It has been shown that endothelial cell adhesion molecules play an important role in the development of coronary atherosclerosis and inflammatory disease. We sought to test whether soluble vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and E-selectin are increased in patients with documented coronary artery disease (CAD). Plasma levels of VCAM-1, ICAM-1 and E-selectin were measured in 40 patients with documented CAD, 20 subjects with angiographically documented normal coronary arteries, and 14 healthy volunteers. Patients with documented CAD exhibited significant elevation of VCAM-1 (535 +/- 227.1 ng/ml, p = 0.0001), E-selectin (69.4 +/- 29.4 ng/ml, p = 0.006), but not ICAM-1 (320.5 +/- 65.1 ng/ml, p = 0.9) concentrations as compared to subjects with normal coronary arteries (252.3 +/- 79.8, 49.7 +/- 22.0 and 311.4 +/- 40.2 ng/ml), and healthy controls (110.0 +/- 17.7, 29.0 +/- 2.0 and 237.5 +/- 46.5 ng/ml), respectively. Soluble markers of endothelial injury are not uniformly increased in patients with documented CAD as compared to those with normal coronary arteries and healthy controls. However, VCAM-1 and E-selectin, but not ICAM-1 could identify endothelial injury in such patients.     

Effect of Tribulus Terrestris L. on Expression of ICAM-1, VCAM-1, E-Selectin and Proteome Profile of Human Endothelial Cells In-Vitro

Background: Atherosclerosis is a chronic inflammation that interferes with blood arteries functions due to the accumulation of low density lipids and cholesterol. Objective: To investigate the effect of aqueous extract and saponin fraction of Tribulus terrestris L. (TT) on the proteome and expression of intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin in the human umbilical vein endothelial cells (HUVEC) and human bone marrow endothelial cell (HBMEC) lines. Methods: Two cell lines were cultured and induced with lipopolysaccharide (LPS). The primed cells were then treated with aqueous extract and saponin fraction of TT. The protein profile of the endothelial cells was assessed under normal and LPS-induced conditions using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and 2D gel electrophoresis (2-DE). The levels of VCAM-1, ICAM-1, and E-selectin were estimated by use of western blotting. Results: LPS-induced HUVECs and HBMECs were shown to significantly increase the expression of ICAM-1, VCAM-1, and E-selectin in comparison to control groups. Our findings revealed that TT extract resulted in significantly more reduced levels of proteom (80 spots) as well as all the three mentioned proteins compared with the effect of saponin fraction alone. Conclusion: TT extract and its saponin fraction exerted anti-inflammatory effects on HUVEC and HBMEC lines and reduced the expression of ICAM-1, VCAM-1, and E-selectin. However, the anti-inflammatory effect of aqueous extract was greater than that of saponin fraction. Therefore, TT could be considered as a potential candidate for the treatment or prevention of atherosclerosis.     

Serum levels of thrombomodulin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin in the acute phase of Plasmodium vivax malaria

Elevated plasma or serum levels of thrombomodulin (TM), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin have been reported in several diseases. However, plasma or serum levels of TM, ICAM-1, VCAM-1, and E-selectin have not been investigated in the acute phase of Plasmodium vivax malaria. Serum TM, ICAM-1, VCAM-1, E-selectin, and creatinine levels were determined in six Japanese patients in the acute phase of vivax malaria and in seven healthy Japanese controls. Parasitemias of the peripheral blood were < 0.1% in five patients and 0.8% in one patient. The patients' mean +/- SD serum levels of TM, ICAM-1, VCAM-1, and E-selectin were 5.7 +/- 1.3 Fujirebio units/ml, 709 +/- 397 ng/ml, 2,112 +/- 782 ng/ml, and 99 +/- 28 ng/ml, respectively, and all were significantly greater than those in the controls (TM; P < 0.005, ICAM-1; P < 0.025, VCAM-1; P < 0.005, E-selectin; P < 0.025). However, no significant difference was identified between patients and controls for serum creatinine values. The serum levels of TM and VCAM-1 were not related to parasitemia. The elevation of serum TM levels suggests that endothelial cell damage occurs in the acute phase of vivax malaria.     

Effect of transdermal hormone replacement therapy on the monocyte chemoattractant protein-1 concentrations and other vascular inflammatory markers and on endothelial function in postmenopausal women

Monocyte chemoattractant protein-1 (MCP-1) is related to the progression of atherosclerosis. However, little is known about the effects of transdermal hormone replacement therapy (HRT) on circulating MCP-1, vascular inflammatory marker concentrations, and endothelial function in postmenopausal women. The effects of transdermal HRT on circulating MCP-1, vascular inflammatory marker concentrations, and endothelium-dependent vasodilation were investigated in postmenopausal women. Thirty-three women received transdermal HRT (continuous 17-beta estradiol patch 36 microg/day plus cyclic oral medroxyprogesterone acetate 2.5 mg/day for 12 days/month) for 12 months, and 27 control patients did not. Brachial artery flow-mediated vasodilation (FMD), assessed by ultrasound, and circulating MCP-1 and vascular inflammatory marker (C-reactive protein, intercellular adhesion molecule-1 [ICAM-1], vascular cell adhesion molecule-1 [VCAM-1], and E-selectin) concentrations were measured before and after 12 months of treatment. In the HRT group, MCP-1 concentrations decreased significantly (p <0.001), and ICAM-1, VCAM-1, and E-selectin concentrations decreased significantly (p <0.01 for all), but C-reactive protein concentrations did not change. MCP-1 and other marker concentrations did not change in the control group. FMD increased significantly in the HRT group (p <0.001) but did not change in the control group. Nitroglycerin-induced vasodilation did not change in either group. In conclusion, transdermal HRT decreased MCP-1 and cell adhesion molecule concentrations and improved endothelial function in postmenopausal women. Transdermal HRT may exert an antiatherosclerotic effect by improving MCP-1 and cell adhesion molecule expression and endothelial function.     

Patterns of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 expression in rabbit and mouse atherosclerotic lesions and at sites predisposed to lesion formation.

The recruitment of mononuclear leukocytes and formation of intimal macrophage-rich lesions at specific sites of the arterial tree are key events in atherogenesis. Inducible endothelial cell adhesion molecules may participate in this process. In aortas of normal chow-fed wild-type mice and rabbits, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), but not E-selectin, were expressed by endothelial cells in regions predisposed to atherosclerotic lesion formation. En face confocal microscopy of the mouse ascending aorta and proximal arch demonstrated that VCAM-1 expression was increased on the endothelial cell surface in lesion-prone areas. ICAM-1 expression extended into areas protected from lesion formation. Hypercholesterolemia induced atherosclerotic lesion formation in rabbits, LDL receptor and apolipoprotein E knockout mice, and Northern blot analysis demonstrated increased steady-state mRNA levels of VCAM-1 and ICAM-1, but not of E-selectin. Immunohistochemical staining revealed that VCAM-1 and ICAM-1 were expressed predominantly by endothelium in early lesions and by intimal cells in more advanced lesions. In early and advanced lesions, staining was most intense in endothelial cells at and adjacent to lesion borders. ICAM-1 staining extended into the uninvolved aorta. These expression patterns were highly reproducible in both species. The only difference was that VCAM-1 expression in endothelium over the central portions of lesions was found frequently in rabbits and rarely in mice. The expression of VCAM-1 by arterial endothelium in normal animals may represent a pathogenic mechanism or a phenotypic marker of predisposition to atherogenesis.     

Elevated levels of soluble E-selectin in patients with IDDM and NIDDM: relation to metabolic control

Summary The adhesion of leucocytes to the endothelium, an early step in atherogenesis, is mediated by cell adhesion molecules. In this study we evaluated the concentration of soluble adhesion molecules in patients with insulin-dependent (IDDM) and non-insulin-dependent diabetes mellitus (NIDDM) and studied its relation to glycaemic control. Soluble adhesion molecules E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) were measured in 31 diabetic patients (18 with IDDM and 13 with NIDDM), 20 hyperlipoproteinaemic patients (10 with type IIa and 10 with type IIb) and 20 healthy subjects. Increased E-selectin concentrations were found in the patients with IDDM and NIDDM and in the hyperlipoproteinaemic patients when compared to the control subjects (p<0.01 for all the groups). ICAM-1 was found to be elevated only in the patients with NIDDM (p<0.01). No significant differences in VCAM-1 concentration were found in the different groups of subjects. The concentration of plasma E-selectin was positively correlated with the glycated haemoglobin (r=0.54, p<0.01) in patients with IDDM and NIDDM. In the same patients E-selectin was not related to the concentrations of plasma lipids in spite of the fact that it was found to be elevated in hyperlipoproteinaemic subjects. The results though preliminary suggest that in diabetic patients the concentration of soluble adhesion molecules and especially of E-selectin may be related to metabolic control.Abbreviations IDDM insulin-dependent diabetes mellitus - NIDDM non-insulin-dependent diabetes mellitus - ICAM-1 intercellular adhesion molecule-1 - VCAM-1 vascular adhesion molecule-1 - AGE advanced glycation end products     

Receptor specificity of clinical Plasmodium falciparum isolates: nonadherence to cell-bound E-selectin and vascular cell adhesion molecule-1

The pathogenicity of Plasmodium falciparum is due largely to the parasite's unique ability to adhere to capillary and postcapillary venular endothelium during the second-half of the 48-hour life cycle. The resulting sequestration of infected erythrocytes (IRBC) in deep vascular beds leads to tissue hypoxia, metabolic disturbances, and organ dysfunction which characterize severe falciparum malaria. Several endothelial receptors of cytoadherence have been identified, but their clinical relevance remains controversial. In the present report, the receptor specificity of 60 clinical P falciparum isolates was determined using transfectants each expressing one of CD36, intercellular adhesion molecule-1 (ICAM-1), E-selectin, and vascular cell adhesion molecule-1 (VCAM-1). All isolates tested adhered to CD36 and ICAM-1, but the adherence to CD36 was at least 10-fold higher. Seven isolates adhered to E-selectin whereas none of 19 isolates adhered to VCAM-1. From a population standpoint, about 30% of IRBC in each isolate adhered to CD36, and 2% to 3% adhered to ICAM-1. The percentage adherent to E-selectin and VCAM-1 was negligible. IRBC selected on CD36 adhered almost exclusively to CD36 whereas 80% to 90% of IRBC selected on ICAM-1 could also adhere to CD36. Selected IRBC did not adhere to E-selectin or VCAM-1. These findings indicate that cytoadherence to multiple endothelial receptors is a rare occurrence with natural P falciparum isolates, but do not exclude a role for the adhesion molecules in promoting other IRBC-endothelial interactions such as rolling under flow conditions. Receptor specificity in vivo may be dictated by the ligand-receptor combination which provides the best survival potential for the parasite.     

Protection from procedural myocardial injury by atorvastatin is associated with lower levels of adhesion molecules after percutaneous coronary intervention: results from the ARMYDA-CAMs (Atorvastatin for Reduction of MYocardial Damage during Angioplasty-Cell Adhesion Molecules) substudy.

OBJECTIVES: The goal of this work was to investigate whether protection from myocardial injury during percutaneous coronary intervention (PCI) by atorvastatin is related to reduction of endothelial inflammatory response. BACKGROUND: In the randomized ARMYDA (Atorvastatin for Reduction of MYocardial Damage during Angioplasty) trial, 7-day pre-treatment with atorvastatin before PCI significantly reduced procedural myocardial injury; mechanisms underlying this effect are not characterized. METHODS: In a planned subanalysis of the ARMYDA trial, a subgroup of 76 patients was blind-tested for measurement of plasma levels of vascular cell adhesion molecule-1 (VCAM-1), intercellular cell adhesion molecule-1 (ICAM-1), and E-selectin: 38 patients belonged to atorvastatin (40 mg/day) and 38 to the placebo arm. Adhesion molecules were evaluated 7 days before intervention, immediately before PCI, and after 8 and 24 h. RESULTS: Reduction of procedural myocardial injury after statin pre-treatment was also confirmed in this subgroup. Intercellular cell adhesion molecule-1, E-selectin, and VCAM-1 levels were not different at randomization and before intervention in either arm. At 8 h, increase of ICAM-1 levels was similar in the 2 arms, whereas 24-h levels were significantly lower in the atorvastatin versus placebo group (282 +/- 56 vs. 325 +/- 70 ng/ml; p = 0.007). Attenuation of E-selectin elevation occurred at 8 h in the atorvastatin group (50 +/- 8 vs. 59 +/- 13 ng/ml; p = 0.002) and became even more significant at 24 h (57 +/- 9 vs. 73 +/- 18 ng/ml; p = 0.0008). Vascular cell adhesion molecule-1 levels were not different at any time point in the 2 arms. CONCLUSIONS: In patients undergoing PCI, reduction of procedural myocardial injury after 7-day pre-treatment with atorvastatin is paralleled by concomitant attenuation of post-procedural increase of ICAM-1 and E-selectin levels; thus, reduction of endothelial inflammatory response may explain this protective effect of statins.     

Circulating adhesion molecules and severity of coronary atherosclerosis

BACKGROUND: Circulating leukocytes are recruited at atherosclerotic sites through a family of adhesion molecules. Circulating forms of adhesion molecules in peripheral blood can be quantified now. OBJECTIVE: To evaluate the relationship between circulating adhesion molecules and severity of coronary atherosclerosis. METHODS: Subjects included 81 patients undergoing diagnostic coronary angiography, 12 of whom had normal coronary arteries (control group). The remaining 69 patients with demonstrable coronary atherosclerosis were divided into two groups by use of Gensini scores, namely mild atherosclerosis (n = 36, Gensini score 1-20) and severe atherosclerosis (n = 33, Gensini score > 20). Serum levels of circulating intercellular adhesion molecule-1 (ICAM-1), vascular cellular adhesion molecule-1 (VCAM-1), and E-selectin of groups measured before angiography were compared. RESULTS: Circulating levels of ICAM-1 in members of mild and severe atherosclerosis groups were significantly higher than those in members of the control group, whereas there was no significant difference among circulating levels of VCAM-1 in members of the three groups. Circulating levels of E-selectin in members of the mild atherosclerosis group were significantly higher than those in members of the severe atherosclerosis and control groups. CONCLUSIONS: These findings suggest that E-selectin is related to the early stage, and ICAM-1 is related to the advanced stage, of coronary atherosclerosis. With progression of atherosclerosis, one-step adhesion by ICAM-1 could become more important than multistep adhesion involving E-selectin, ICAM-1, and VCAM-1. These molecules may serve as markers for severity of coronary atherosclerosis.     

Comparison of serum concentrations of soluble adhesion molecules in diabetic microangiopathy and macroangiopathy.

AIMS: To clarify the correlation between serum concentrations of soluble adhesion molecules and diabetic microangiopathy or macroangiopathy in patients with Type 2 diabetes. METHODS: Patients with diabetic retinopathy and intima-media thickness of common carotid artery (CCA-IMT) < 1.1 mm were classified as the microangiopathy group (n = 62). Patients with CCA-IMT > or = 1.1 mm and without retinopathy were classified as the macroangiopathy group (n = 95). Patients with CCA-IMT < 0.9 mm and without retinopathy were assigned to the no complications group (n = 139). Clinical characteristics and soluble intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin levels were compared between the groups. RESULTS: Patients with microangiopathy had a significantly longer duration of diabetes, were hypertensive and more likely to have a positive family history of diabetes than the control group. Patients with macroangiopathy were more likely to be smokers, hypertensive, and have a family history of hypertension. Soluble ICAM-1, VCAM-1, and E-selectin levels were significantly higher in the microangiopathy group than in the control group. Soluble VCAM-1 and E-selectin levels, but not ICAM-1 levels, were significantly elevated in the macroangiopathy group. These results were unchanged after adjustment for age, sex, duration of diabetes, blood pressure, HbA1c, HDL-cholesterol, and smoking status. CONCLUSIONS: Our results suggest that soluble adhesion molecules are related to both diabetic micro- and macroangiopathy. The relative contributions of adhesion molecules may be greater in the former than latter patients with Type 2 diabetes.     

Angiopoietin-1 reduces VEGF-stimulated leukocyte adhesion to endothelial cells by reducing ICAM-1, VCAM-1, and E-selectin expression

Vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang1) are potent vasculogenic and angiogenic factors that hold promise as a means to produce therapeutic vascularization and angiogenesis. However, VEGF also acts as a proinflammatory cytokine by inducing adhesion molecules that bind leukocytes to endothelial cells, an initial and essential step toward inflammation. In the present study, we used human umbilical vascular endothelial cells (HUVECs) to examine the effect of Ang1 on VEGF-induced expression of three adhesion molecules: intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin. Interestingly, Ang1 suppressed VEGF-induced expression of these adhesion molecules. Furthermore, Ang1 reduced VEGF-induced leukocyte adhesion to HUVECs. These results demonstrate that Ang1 counteracts VEGF-induced inflammation by reducing VEGF-induced endothelial adhesiveness.     

Endothelial tetraspanin microdomains regulate leukocyte firm adhesion during extravasation

Tetraspanins associate with several transmembrane proteins forming microdomains involved in intercellular adhesion and migration. Here, we show that endothelial tetraspanins relocalize to the contact site with transmigrating leukocytes and associate laterally with both intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). Alteration of endothelial tetraspanin microdomains by CD9-large extracellular loop (LEL)-glutathione S-transferase (GST) peptides or CD9/CD151 siRNA oligonucleotides interfered with ICAM-1 and VCAM-1 function, preventing lymphocyte transendothelial migration and increasing lymphocyte detachment under shear flow. Heterotypic intercellular adhesion mediated by VCAM-1 or ICAM-1 was augmented when expressed exogenously in the appropriate tetraspanin environment. Therefore, tetraspanin microdomains have a crucial role in the proper adhesive function of ICAM-1 and VCAM-1 during leukocyte adhesion and transendothelial migration.     

The effects of dipyridamole stress test on plasma levels of soluble adhesion molecules intracellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin and L-selectin in patients with ischemic heart disease and patients with syndrome X.

BACKGROUND: Adhesion of activated leukocytes to the endothelium as a result of myocardial ischemia/reperfusion has been shown to be involved in the development of tissue injury. Leukocyte adhesion to the endothelium occurs via adhesion molecules expressed on the surface of both cell types. Upon cell activation these proteins may be released into the circulation and measured in a soluble form. AIM: To verify whether the dipyridamole stress test, performed in patients with ischemic heart disease (IHD) and in patients with syndrome X, modifies plasma levels of the soluble adhesion molecules vascular cell adhesion molecule-1 (VCAM-1), intracellular adhesion molecule-1 (ICAM-1), E-selectin and L-selectin. METHODS: Plasma levels of the soluble endothelial adhesion molecules ICAM-1, VCAM-1 and E-selectin, as well as of the soluble leukocyte adhesion molecule L-selectin, were measured in venous blood samples taken before and 7 min after administration of dipyridamole in patients with IHD, patients with syndrome X and healthy individuals. Myocardial perfusion was evaluated using single photon emission tomography. The plasma levels of soluble VCAM-1, ICAM-1, E-selectin and L-selectin were all measured using enzyme-linked immunosorbent assays. RESULTS: After infusion of dipyridamole, plasma levels of ICAM-1 increased significantly in patients with IHD, whereas they remained unchanged in patients with syndrome X and in the control group. In patients with IHD, the initial plasma levels of VCAM-1, E-selectin and L-selectin, before administration of dipyridamole, were higher than those observed in patients with syndrome X and than those in the control group. Plasma levels of soluble VCAM-1, E-selectin and L-selectin decreased significantly in patients with IHD following the dipyridamole stress test, whereas they remained unchanged in patients with syndrome X, and in the control group. CONCLUSION: In patients with IHD, administration of dipyridamole induces myocardial ischemia resulting in modification of plasma levels of the soluble adhesion molecules.