Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042373 (vascular disease)
 17,070 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

There is increasing evidence that direct pathobiological events in the vessel wall play an important role in vascular disease. An important mechanism involves the perturbation of the homeostatic balance between NO and reactive oxygen species. Increased reactive oxygen species can inactivate NO and produce peroxynitrite. Angiotensin II is a potent mediator of oxidative stress and stimulates the release of cytokines and the expression of leukocyte adhesion molecules that mediate vessel wall inflammation. Inflammatory cells release enzymes (including ACE) that generate angiotensin II. Thus, a local positive-feedback mechanism could be established in the vessel wall for oxidative stress, inflammation, and endothelial dysfunction. Angiotensin II also acts as a direct growth factor for vascular smooth muscle cells and can stimulate the local production of metalloproteinases and plasminogen activator inhibitor. Taken together, angiotensin II can promote vasoconstriction, inflammation, thrombosis, and vascular remodeling. In this article, we propose a model that unifies the interrelationship among cardiovascular risk factors, angiotensin II, and the pathobiological mechanisms contributing to cardiovascular disease. This model may also explain the beneficial effects of ACE inhibitors on cardiovascular events beyond blood pressure reduction.
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PMID:Theodore Cooper Lecture: Tissue angiotensin and pathobiology of vascular disease: a unifying hypothesis. 1130 1

Insulin resistance is a uniform finding in type 2 diabetes, as are abnormalities in the microvascular and macrovascular circulations. These complications are associated with dysfunction of platelets and the neurovascular unit. Platelets are essential for hemostasis, and knowledge of their function is basic to understanding the pathophysiology of vascular disease in diabetes. Intact healthy vascular endothelium is central to the normal functioning of smooth muscle contractility as well as its normal interaction with platelets. What is not clear is the role of hyperglycemia in the functional and organic microvascular deficiencies and platelet hyperactivity in individuals with diabetes. The entire coagulation cascade is dysfunctional in diabetes. Increased levels of fibrinogen and plasminogen activator inhibitor 1 favor both thrombosis and defective dissolution of clots once formed. Platelets in type 2 diabetic individuals adhere to vascular endothelium and aggregate more readily than those in healthy people. Loss of sensitivity to the normal restraints exercised by prostacyclin (PGI(2)) and nitric oxide (NO) generated by the vascular endothelium presents as the major defect in platelet function. Insulin is a natural antagonist of platelet hyperactivity. It sensitizes the platelet to PGI(2) and enhances endothelial generation of PGI(2) and NO. Thus, the defects in insulin action in diabetes create a milieu of disordered platelet activity conducive to macrovascular and microvascular events.
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PMID:Platelet dysfunction in type 2 diabetes. 1147 89

In the present study we have shown that adults with Down syndrome have reduced plasminogen activator inhibitor type-1 in blood compared with control subjects matched for age, gender, and body mass. Reduced plasminogen activator inhibitor type-1 may explain the low incidence of atherosclerotic vascular disease and its complications that are attributable to plaque instability, such as myocardial infarction and unstable angina, in subjects with Down syndrome, despite an ever-increasing life expectancy.
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PMID:Plasminogen activator inhibitor type 1 in adults with Down syndrome and protection against macrovascular disease. 1200 63

We aimed to investigate significant correlations of insulin resistance with thrombotic factors in South Asians with stroke. Correlations of Homeostasis Model Assessment (HOMA)(as a surrogate of insulin resistance) were analysed with 6 thrombotic factors in 140 South Asian patients with a history of confirmed (by computerised tomography) ischaemic stroke. Age and sex adjusted HOMA was correlated to waist-hip ratio (r = 0.38, p = 0.0001), triglycerides (r = 0.22, p = 0.03), systolic blood pressure (r = 0.21, p = 0.04), tissue plasminogen activator (t-PA) (r = 0.22, p = 0.04); plasminogen activator inhibitor 1(PAI-1) (r = 0.26, p = 0.02); fibrinogen (r = 0.25, p = 0.02); and factor VII antigen (r = 0.21, p = 0.06). On regression analysis, with HOMA as dependent variable and significant correlates as independent variables in the model, HOMA was independently associated with PAI-1 antigen. There is extensive clustering of metabolic and thrombotic factors with insulin resistance in South Asian patients with ischaemic stroke, which may contribute to high prevalence of vascular disease in this population.
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PMID:Clustering of thrombotic factors with insulin resistance in South Asian patients with ischaemic stroke. 1252 44

Thrombomodulin (TM) slows down the interaction rate between thrombin and plasminogen activator inhibitor 1 (PAI-1). We now show that the 12-fold reduced inhibition rate in the presence of TM does not result from an altered distribution between PAI-1 cleavage and irreversible complex formation. Surface plasmon resonance (SPR) revealed an over 200-fold reduced affinity of TM for thrombin-VR1tPA as compared to thrombin, demonstrating the importance of the VR1 loop in the interaction of thrombin with both TM and PAI-1. Furthermore, in contrast to ATIII, PAI-1 was not able to bind the thrombin/TM complex demonstrating complete competitive binding between PAI-1 and TM. Kinetic modeling on the inhibitory effect of TM confirms a mechanism that involves complete steric blocking of the thrombin/PAI-1 interaction. Also, it accurately decribes the biphasic inhibition profile resulting from the substantial reduction of the extremely fast rate of reversible Michaelis complex formation, which is essential for efficient inhibition of thrombin by PAI-1. Vitronectin (VN) is shown to partially relieve TM inhibitory action only by vastly increasing the initial rate of interaction between free thrombin and PAI-1. In addition, SPR established that solution-phase PAI-1/VN complexes and non-native VN (extracellular matrix form) bind TM directly via the chondroitin sulphate moiety of TM. Collectively, these results show that VR1 is a subsite of exosite 1 on thrombin's surface, which regulates exclusive binding of either PAI-1 or TM. This competition will be physiologically significant in controlling the mitogenic activity of thrombin during vascular disease.
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PMID:A steady-state competition model describes the modulating effects of thrombomodulin on thrombin inhibition by plasminogen activator inhibitor-1 in the absence and presence of vitronectin. 1270 53

To elucidate the biological characteristics of adipose tissue, we analyzed the gene expression profile of visceral and subcutaneous fat. Unexpectedly, adipose tissue, especially visceral fat, expressed a variety of genes for secretory proteins. About 30% of the genes expressed in visceral adipose tissue encoded secretory proteins and most were biologically active molecules, which we called adipocytokines. We found plasminogen activator inhibitor type 1 and heparin binding EGF-like growth factor. Production of these atherogenic adipocytokines was shown to increase with the accumulation of visceral fat, which may be one of the mechanisms of vascular disease in visceral obesity. We found a unique and novel collagen-like protein, adiponectin, encoded by the most abundantly expressed gene in adipose tissue, termed APM1 (adipose most abundant gene transcript-1). Plasma levels of adiponectin ranged from 0.3 to approximately 3 mg/dl but were decreased in patients with visceral obesity, type 2 diabetes and coronary artery disease (CAD). Screening for mutations in the adiponectin gene revealed that patients carrying a missense mutation showed markedly decreased plasma levels of adiponectin and had CAD. These data suggest that hypoadiponectinemia may be considered an important risk factor for CAD. Cell biology studies revealed that adiponectin has a potent inhibitory effect on the expression of adhesion molecules in endothelial cells and an inhibitory effect on the expression in macrophages. In order to confirm these antidiabetic and antiatherogenic functions of adiponectin, we developed adiponectin knockout mice. Adiponectin knockout mice showed severe insulin resistance and impaired glucose metabolism when fed a high-fat, high-sucrose diet. Knockout mice also developed intimal thickening in response to endothelial injury.
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PMID:Importance of adipocytokines in obesity-related diseases. 1467 98

Complex inter-relationships between age-associated illnesses, such as vascular disease and Alzheimer's disease (AD), suggest that biological and genetic pathways may be worthy of examination in centenarian populations to provide insights into human longevity. This is also borne out by the involvement of lipoprotein metabolism and a number of vascular genetic risk factors. Repeated findings of a higher frequency of the apolipoprotein E (APOE) epsilon4 allele in middle-aged subjects compared with centenarians were reported. Furthermore, we have also shown how in different populations there is a significant trend in reduction of serum APOE levels from APOE epsilon2- to epsilon4-carrier as well as significant differences in serum APOE levels respect to age in epsilon4-carriers but only after adjustment for HDL cholesterol. In contrast, findings of increased prevalence of the angiotensin I converting enzyme 1 (ACE1) D allele in French centenarians have not been replicated, suggesting the possibility that regional differences may occur in ACE1(*)D frequency within Europe in centenarians, as has been recently reported for APOE epsilon2 and epsilon4 alleles. A number of studies have examined the potential role in longevity of other genes involved in vascular risk, haemostasis, and blood pressure regulation [methyltetrahydrofolatereductase (MTHFR), apolipoprotein A1 (APOA-I), apolipoprotein C3 (APOC-III), apolipoprotein A4 (APOA-IV), paraoxonase 1 (PON1), plasminogen activator inhibitor type I (PAI-1)], with contrasting results. While further studies are needed to confirm the possible role of APOE concentration as putative longevity factor, this paper provides an overview of genetic vascular factors potentially involved in human longevity.
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PMID:Vascular genetic factors and human longevity. 1501 61

Patients with Type 2 diabetes (T2DM) are at high risk of morbidity and mortality from cardiovascular complications, and hypoglycaemia increases this risk. Furthermore, other metabolic parameters exacerbate cardiovascular risk in these patients. The aim of the study was to compare the metabolic effects of glimepiride and metformin in patients with T2DM. We evaluated 164 patients with T2DM (80 males, 84 females) in a multicentre, randomised, controlled, open, parallel group study comparing glimepiride with metformin. Eighty-one patients (aged 56+/-10 yr) received glimepiride (3+/-1 mg/d); 83 patients (aged 58+/-9 yr) received metformin (2500+/-500 mg/d). Patients had been diagnosed for < or = 6 months; they were non-smokers; had no hypertension or coronary heart disease; were not taking hypolipidaemic drugs, diuretics, beta-blockers or thyroxin; and had normal renal function. Metabolic parameters were measured after 6 and 12 months of treatment. Glimepiride significantly lowered lipoprotein(a) [Lp(a)] and homocysteine levels (HCT) at 6 and 12 months. Both glimepiride and metformin lowered plasminogen activator inhibitor Type 1 (PAI-1) at 12 months and significantly improved levels of glycosylated haemoglobin, fasting plasma glucose and post-prandial plasma glucose after 6 and 12 months. Metformin significantly lowered fasting plasma insulin and postprandial plasma insulin. Glimepiride and metformin also reduced levels of other metabolic parameters in patients with T2DM. In particular, glimepiride significantly reduced HCT, Lp(a), and PAI-1 levels, important metabolic risk factors for atherosclerotic vascular disease. These reductions may be owing to improved glucose metabolism, but it cannot be excluded that these drugs have a direct effect on additional metabolic parameters.
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PMID:Metabolic variations with oral antidiabetic drugs in patients with Type 2 diabetes: comparison between glimepiride and metformin. 1533 91

Hyperhomocysteinemia is a risk factor for arterial vascular disease and venous thrombosis. The pathophysiology of this relation is unclear, but several studies suggest that hyperhomocysteinemia impairs endothelial function. We examined the effect of homocysteine lowering by B-vitamin supplementation on tissue plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI) and von Willebrand factor (vWf)--markers of endothelial dysfunction--in hyperhomocysteinemic and normohomocysteinemic volunteers. A total of 123 healthy volunteers were randomized to placebo or B-vitamins (5 mg folic acid, 0.4 mg hydroxycobalamin and 50 mg pyridoxine) daily for 8 weeks. Before and after the intervention period, blood samples were taken for measurements of homocysteine, tPA, PAI and vWf. There was no evident association between homocysteine concentration and concentrations of markers of endothelial dysfunction at baseline. The mean reduction of homocysteine concentration was 31% (95%CI 22.7 to 39.1) in the B-vitamin group compared to 3% reduction in the placebo group. Concentrations of tPA, PAI and vWf did not change after supplementation of B-vitamins. In conclusion, the results of our study show that homocysteine reduction by B-vitamin supplementation has no effect on markers of endothelial dysfunction in healthy volunteers.
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PMID:The effect of homocysteine reduction by B-vitamin supplementation on markers of endothelial dysfunction. 1554 37

There is evidence to suggest that certain shared features exist in the pathogenesis of vascular disease and Alzheimer disease (AD) in the general population. In Down syndrome (DS) all adults over the age of 40 years develop sufficient neuropathology for a diagnosis of AD. However, vascular disease is not as common in DS as it is in the general population, particularly with respect to the development of atheromas. We discuss biological mechanisms and risk factors that may be common to both diseases including cholesterol metabolism, inflammation, plasminogen activator inhibitor and apolipoprotein E (Apo E). The study of individuals with DS may help to identify common pathogenic links as well as a disassociation between vascular disease and AD.
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PMID:Alzheimer disease and Down syndrome: factors in pathogenesis. 1563 17


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