heparitin-sulfate and Carotid-Artery-Diseases

Ischemic stroke patients subtyped as of undetermined cause (SUC) usually outnumber those with determined cause subtypes. Etiological stroke classifications may lead to neglect of parallel, noncausative findings. Atherosclerosis progresses over decades and is associated with high morbidity and mortality in young stroke patients in long-term follow-up studies. We compared the prevalence of carotid atherosclerosis in all TOAST subtypes among young patients with acute ischemic stroke.. We investigated 150 patients aged 15-60 years with documented acute ischemic stroke, and 84 controls free of cardiovascular disease. Stroke etiology was classified according to TOAST criteria. Carotid intima-media thickness (cIMT) measurements were obtained from 12 standardized multiangle measurements in the common carotid artery, carotid bifurcation, and internal carotid artery.. The causes of stroke were 5.3% large-artery atherosclerosis (LAA), 26.7% cardioembolism, 21.3% small-artery occlusion (SAO), 10% stroke of other determined cause, and 36.7% stroke of undetermined cause (SUC). cIMT was increased in patients with LAA (1.56 mm, P = .002), SAO (1.11 mm, P = .006), and SUC (1.10 mm, P = .004) compared to controls (cIMT 0.86 mm). Segmental cIMT distribution differed across stroke subtypes, age groups, and sexes.. Atherosclerotic disease is prevalent in the majority of young and middle-aged ischemic stroke patients, requiring determined investigation and aggressive treatment of modifiable risk factors.

Topics: Adolescent; Adult; Age Factors; Carotid Artery Diseases; Carotid Intima-Media Thickness; Chondroitin Sulfates; Dermatan Sulfate; Female; Fibrinolytic Agents; Heparitin Sulfate; Humans; Longitudinal Studies; Male; Middle Aged; Neuroimaging; Norway; Stroke; Young Adult

The endothelial glycocalyx, a glycosaminoglycan layer located on the apical surface of vascular endothelial cells, has been shown to be important for several endothelial functions. Previous studies have documented that the glycocalyx is highly abundant in the mouse common carotid region, where the endothelium is exposed to laminar shear stress, and it is resistant to atherosclerosis. In contrast, the glycocalyx is scarce or absent in the mouse internal carotid sinus region, an area exposed to nonlaminar shear stress and highly susceptible to atherosclerosis. On the basis of these observations, we hypothesized that the expression of components of the endothelial glycocalyx is differentially regulated by distinct hemodynamic environments. To test this hypothesis, human endothelial cells were exposed to shear stress waveforms characteristic of atherosclerosis-resistant or atherosclerosis-susceptible regions of the human carotid, and the expression of several components of the glycocalyx was assessed. These experiments revealed that expression of several components of the endothelial glycocalyx is differentially regulated by distinct shear stress waveforms. Interestingly, we found that heparan sulfate expression is increased and evenly distributed on the apical surface of endothelial cells exposed to the atheroprotective waveform and is irregularly present in cells exposed to the atheroprone waveform. Furthermore, expression of a heparan sulfate proteoglycan, syndecan-1, is also differentially regulated by the two waveforms, and its suppression mutes the atheroprotective flow-induced cell surface expression of heparan sulfate. Collectively, these data link distinct hemodynamic environments to the differential expression of critical components of the endothelial glycocalyx.

Topics: Atherosclerosis; Carotid Artery Diseases; Cells, Cultured; Endothelial Cells; Gene Expression Regulation; Glycocalyx; Hemodynamics; Heparitin Sulfate; Humans; Shear Strength; Stress, Mechanical; Syndecan-1

Heparan sulfate in the extracellular matrix of the artery wall has been proposed to possess anti-atherogenic properties by interfering with lipoprotein retention, suppression of inflammation, and inhibition of smooth muscle cell growth. Previously, the amount of heparan sulfate in atherosclerotic lesions from humans and animals has been shown to be reduced but the identity or identities of the heparan sulfate molecules being down regulated in this disease are not known. In this study, atherosclerotic lesions were retrieved from 44 patients undergoing surgery for symptomatic carotid stenosis. Normal iliac arteries from organ donors were used as controls. Analysis of the specimens by gene microarray showed a selective reduction in perlecan gene expression, whereas, expression of the other heparan sulfate proteoglycans in the artery wall, agrin and collagen XVIII, remained unchanged. Expression of the large chondroitin sulfate proteoglycan, versican, also remained unchanged. Real-time PCR confirmed the decrease in perlecan gene expression and the unchanged expression of versican. The findings were supported by immunohistochemical analysis demonstrating a reduced accumulation of both perlecan core protein and heparan sulfate in carotid lesions. The study demonstrates a reduction of perlecan mRNA-expression and protein deposition in human atherosclerosis, which in part explains the low levels of heparan sulfate in this disease.

Topics: Aged; Aged, 80 and over; Carotid Artery Diseases; Carotid Stenosis; Gene Expression Regulation; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Immunohistochemistry; Middle Aged; Polymerase Chain Reaction; RNA