Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.15.1 (ACE)
18,300 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Healthy vascular endothelium is a powerful generator of nitric oxide (NO), prostacyclin (PGI2), prostaglandin E2 (PGE2), and plasminogen activator (t-PA). These endothelial products protect vascular wall against aggression from activated blood platelets and leukocytes. In particular they protect against thrombosis, promote thrombolysis, maintain tissue perfusion, and inhibit remodeling of vascular and cardiac walls. Endothelial dysfunction appears on one hand as suppression in the release of the above mediators, and on the other as deleterious discharge of prostaglandin endoperoxides (PGH2, PGG2), superoxide anion O2-, peroxynitrite (ONOO-), and plasminogen activator inhibitor (PAI-1). Our data point to endothelial bradykinin (Bk) as a trigger for protective endothelial mechanisms. In cultured endothelial cells (CEC) Bk through kinin B2 receptors raised in a concentration-dependent manner (1pM-10 nM) free cytoplasmic calcium ions [Ca2+]i. This rise was accompanied by the release of NO as quantified by a porphyrinic sensor. Other endothelial agonists were weaker-stimulators of [Ca2+]i than Bk. In vivo we analyed the effects of exogenous Bk and of amplifiers of endogenous Bk, such as perindopril and quinapril ("tissue type" angiotensin converting enzyme inhibitors, ACE-I) on endothelial function using our original thrombolytic bioassay and EIA assays for 6-keto-PGF1alpha and t-PA antigen. A major difference found between exogenuous Bk and endogenous Bk (that rendered by "tissue ACE-I") was a) prolonged thrombolytic action (> 4h) of quinapril or perindopril. Moreover, only exogenous Bk evoked an immediate and profound hypotensive action. In vivo, Bk-induced thrombolysis was B2 kinin receptor-dependent, PGI2-mediated. The unexpected action of Bk came to light in CEC. Then appeared incubated for 4 h increased expression of mRNAs for haemoxygenase (HO-1), cyclooxygenase 2 (COX-2), prostaglandin E synthase (PGE-S), but hardly for nitric oxide synthase 2(NOS-2). We hypothesize that a network of interactions of Bk-induced enzymes may constitute a delayed phase of Bk effects in the endothelium, whereas the primary phase would be activation by BK of [Ca2+]i-dependent constitutive endothelial enzymes. In blood-perfused rat endotoxemic lungs, NO is the most eminent cytoprotective mediator. Summing up, in peripheral circulation endogenous Bk is the most efficient activator of protective endothelial function. Thrombolytic action of "tissue-type" ACE-Is relies on receptor B-2-mediated, [Ca2+]i-dependent release of PGI2. Bk also may act as a "microcytokine" by inducing mRNAs for HO-1, COX-2, or PGE-S. Activation of HO-1 may lead to a deficiency in intracellular heme required as a cofactor for both COX and NOS. This network of interactions triggered by Bk call for further studies.
...
PMID:Bradykinin as a major endogenous regulator of endothelial function. 1205 3

Thrombus formation and degradation is partly due to a complex interplay between tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor 1 (PAI-1). There is accumulating evidence that plasma levels of t-PA and PAI-1 may be influenced by an interaction between the fibrinolytic and renin-angiotensin systems. The goal of this study was to conduct an exploratory data analysis to determine whether there is evidence that the relationship (i.e. correlation) between plasma t-PA and PAI-1 is influenced by interactive effects of the angiotensin converting enzyme (ACE) insertion/deletion (I/D) and plasminogen activator inhibitor 1 (PAI-1) 4G/5G polymorphisms in a sample of 50 unrelated African Americans and 117 unrelated Caucasians. In a single-locus analysis, no evidence for heterogeneity of plasma t-PA and PAI-1 correlations among either ACE I/D or PAI-1 4G/5G genotypes was detected. However, using the combinatorial partitioning method for exploratory data analysis, we identified evidence that is suggestive of heterogeneity of plasma t-PA and PAI-1 correlations among multilocus ACE I/D and PAI-1 4G/5G genotypes in African American females, Caucasian females, Caucasian males, but not African American males. From these results, we propose as a working hypothesis that the correlation between plasma t-PA and PAI-1 may be dependent on epistatic effects of the ACE I/D and PAI-1 4G/5G polymorphisms. This study supports the idea that interactions between the fibrinolytic and renin-angiotensin systems play an important role in the genetic architecture of plasma t-PA and PAI-1.
...
PMID:The relationship between plasma t-PA and PAI-1 levels is dependent on epistatic effects of the ACE I/D and PAI-1 4G/5G polymorphisms. 1212 88

Regulation of vascular tone by the endothelium is abnormal in patients with heart failure and contributes to the characteristic peripheral vasoconstriction and increased afterload. This endothelial dysfunction is mediated through several endothelium-derived factors, including nitric oxide; there is an important interplay between the endothelium and the renin angiotensin system. The benefits of ACE inhibition in heart failure relate, in part, to a reduction in ischemic events which may be mediated by improvements in endothelial function and the endothelium derived fibrinolytic parameters: tissue plasminogen activator (t-PA) and its inhibitor, plasminogen activator inhibitor type 1 (PAI-1). In addition to potential improvements in the regulation of vasomotion, ACE inhibitor therapy may increase bradykinin induced t-PA release and/or reduce angiotensin II mediated PAI-1 release. Recent evidence suggests that both angiotensin II type 1 receptor (AT(1)) antagonism and ACE inhibition improve basal fibrinolytic parameters in patients with heart failure which may facilitate the acute endogenous fibrinolytic response. 1999 by CHF, Inc.
...
PMID:The renin angiotensin system and endothelial dysfunction in chronic heart failure: role of endogenous fibrinolysis. 1218 94

ACE inhibition reduces plasminogen activator inhibitor-1 (PAI-1), a risk factor for myocardial infarction, whereas the effect of angiotensin receptor antagonism on PAI-1 is uncertain. The present study compares the time course of effects of ACE inhibition and angiotensin type 1 (AT1) receptor antagonism on morning plasma PAI-1 antigen. Blood pressure and endocrine, metabolic, and fibrinolytic variables were measured in 20 insulin-resistant (defined by fasting glucose >8.3 mmol/L, body mass index >28 kg/m2, or fasting serum triglyceride > or =2.8 mmol/L) hypertensive subjects (mean age, 47.9+/-2.1 years) (1) before and after 1 week of hydrochlorothiazide 12.5 mg/d, and (2) before and 1, 3, 4, and 6 weeks after addition of ramipril (escalated to 10 mg/d) or losartan (escalated to 100 mg/d). Hydrochlorothiazide decreased systolic (P=0.011) and diastolic (P=0.019) pressure. Ramipril (from 133.6+/-5.1/94.5+/-2.4 to 127.0+/-3.1/91.4+/-3.3 mm Hg) or losartan (from 137.0+/-3.9/93.1+/-2.9 to 123.7+/-2.6/86.4+/-2.1 mm Hg) further reduced systolic (P=0.009) and diastolic (P=0.037) pressure. The pressure effects of the 2 drugs were similar. Hydrochlorothiazide increased plasma PAI-1 (P=0.013) but not tissue-type plasminogen activator (tPA) (P=0.431) antigen. Addition of either ramipril or losartan significantly decreased plasma PAI-1 antigen (P=0.046). However, the effect of losartan on PAI-1 antigen was not sustained throughout the 6-week treatment period, such that there was a significant drugxtime interaction (P=0.043). tPA antigen decreased during either ramipril or losartan (P=0.032), but tPA activity decreased only during losartan (P=0.018). Short-term interruption of the renin-angiotensin-aldosterone system by either ACE inhibition or AT1 receptor antagonism decreases PAI-1 antigen, but the duration of this effect is greater for ACE inhibition than for AT1 receptor antagonism.
...
PMID:ACE inhibition versus angiotensin type 1 receptor antagonism: differential effects on PAI-1 over time. 1246 70

NK3201 is an orally active chymase inhibitor. Its inhibitory activity leads to formation of acyl-intermediate between active serine residue of the enzyme and di-ketone structure of NK3201. NK3201 inhibits human, dog and hamster chymases with IC(50) of 2.5, 1.2, and 28 nM, respectively. On the other hand, NK3201 does not inhibit other types of serine proteases, tryptase, thrombin, elastase, plasmin, and plasminogen activator. In dogs, at 8 h after oral administration of NK3201, 1 mg/kg, the drug levels in plasma, heart, and aorta reached 470, 195, and 78 nM, respectively. In a dog model NK3201, 5 mg/kg/day, increased chymase activity in grafted veins, and suppressed vascular proliferation. After balloon injury in dog vessels, chymase activity was increased locally, in the injured artery, and NK3201, 1 mg/kg/day was effective in preventing vascular proliferation. On the other hand, NK3201, unlike angiotensin converting enzyme inhibitors or angiotensin II receptor blockers, did not affect blood pressure. These findings indicate that local angiotensin II production by chymase is involved only in vascular proliferation, as seen in the injured vessels. Therefore, NK3201 may be useful for preventing vascular proliferation without affecting blood pressure.
...
PMID:Application of a chymase inhibitor, NK3201, for prevention of vascular proliferation. 1293 Dec 53

A number of experimental and clinical investigations support the notion that angiotensin-converting enzyme inhibitor (ACEi) and angiotensin II type 1 receptor blocker (ARB) compounds attenuate renal fibrosis. Fibrosis can be attenuated by either suppressing matrix formation or facilitating matrix degradation. In this study, drugs of ACEi and ARB classes were tested for their ability to facilitate matrix degradation in the kidney. A murine model system in which cyclosporin A (CsA) treatment for a specified period caused interstitial matrix deposition in the kidney was used. CsA was then discontinued, and experimental procedures were initiated to investigate matrix degradation. Benazepril, an ACEi, facilitated matrix degradation via the bradykinin (BK) B2 receptor on tubular epithelial cells in the kidney, whereas CGP-48933, an ARB, did not. In this murine model of CsA nephropathy under ACE blockade, plasminogen activator inhibitor-1 (PAI-1) expression was decreased in tubular epithelial cells, possibly leading to conversion of plasminogen to plasmin by plasminogen activator and subsequent activation of matrix metalloproteinases. These findings were confirmed in this study by measurements of plasmin activity, collagenolytic activity, and matrix metalloproteinase activities in the kidneys. In tubular epithelial cells stimulated in vitro, BK suppressed PAI-1 gene expression. All of these results suggest that ACEi can decrease PAI-1 expression via BK, thereby facilitating matrix degradation via activation of degradative enzymes to reduce interstitial matrix deposition.
...
PMID:Bradykinin decreases plasminogen activator inhibitor-1 expression and facilitates matrix degradation in the renal tubulointerstitium under angiotensin-converting enzyme blockade. 1534 2

The spontaneously hypertensive stroke-prone rat (SHR-SP) is an experimental model of malignant hypertension which lead to secondary alterations of the extracellular matrix. Our aim was to determine ACE-inhibitor related changes of proteases involved in the reconstruction of the extracellular matrix in the brain. Twelve SHR-SP rats were randomized into two groups. Each group was treated with either an antihypertensive dose of ramipril or placebo for 6 months. Brain tissue plasminogen activator (t-PA) and urokinase (u-PA) were quantified by using casein-dependent plasminogen zymography, matrix metalloproteinase (MMP)-2 and MMP-9, by MMP-zymography, and tissue inhibitor of MMP (TIMP)-1 and -2, by reverse zymography. The amounts of u-PA, t-PA, and MMPs were significantly reduced in animals treated with ACE inhibitor. Plasminogen zymography showed a 39% reduction of u-PA in the basal ganglia (p < 0.0001); t-PA expression was reduced by 26% in the cortex and by 33% in the basal ganglia (p < 0.0001). MMP-2 expression was reduced by 15% in the cortex (p < 0.05) and by 10% in the basal ganglia (p < 0.05); MMP-9 expression significantly decreased by 37% in the cortex and by 25% in the basal ganglia (p < 0.0001 each). No differences were observed in the amount of TIMP-1 or TIMP-2. These findings provide new insights into the biochemical mechanisms underlying extracellular matrix proliferation and its modulation by ACE inhibitors. Therapeutic alterations that influence the proteolytic systems might prove important in the prevention of extracellular matrix accumulation and secondary microvascular vessel wall changes.
...
PMID:ACE inhibition reduces activity of the plasminogen/plasmin and MMP systems in the brain of spontaneous hypertensive stroke-prone rats. 1572 Dec 22

Due to excessive salt and water retention, hypertension often becomes refractory in patients undergoing peritoneal dialysis (PD). Management of high blood pressure (BP) appears to be of particular importance in such patients because of its substantial impact on the patients' prognosis. However, attempts to control hypertension in PD patients have not been successful in most cases. In this regard, the present study aimed to address the adequacy of current antihypertensive therapy for PD patients. A new antihypertensive strategy expected to improve the outcome was tested on the assumption that treatment with either angiotensin converting enzyme inhibitor (ACE-I) or angiotensin receptor blocker (ARB) in the evening together with alpha1-blocker at bed time and long-acting Ca channel blocker (CCB) in the morning might ameliorate BP control associated with morning hypertension. Enrolled in the present study were 40 patients whose BP was evaluated by both office and home measurement. Due to an emerging concern about morning hypertension, home BP measured early in the morning was used for the analysis. Each patient was categorized into the following four groups in accordance with office and home BP: well-controlled, poorly-controlled, white-coat and masked (opposite to white-coat), hypertension. After the observation period, 28 patients with refractory hypertension were allocated to intensive antihypertensive therapy in which ARB or ACE-I previously prescribed in the morning or daytime was shifted to the night. In addition, alpha1-blocker was given at bed time. Furthermore, long-acting CCB and diuretics were shifted to the morning. The patients were then followed up for 4-6 months. The results were as follows: 1) Of the total number of 40 PD patients, systolic hypertension was noted in 50% of cases by office BP and in 80% by home BP. The former was less frequent than the latter (p=0.0047, n=40). Similarly, diastolic hypertension was noted in 20% by office BP and in 45% by home BP. The former was less frequent than the latter (p=0.0045, n=40 by McNemar's analysis). The distribution of BP control categories was well-controlled in 11%, poorly-controlled in 42%, masked hypertension in 39% and white-coat hypertension in 8% when determined by systolic BP. The distribution was well-controlled in 45%, poorly-controlled in 13%, masked hypertension in 34% and white-coat hypertension in 8% of cases when determined by diastolic BP. 2) In 28 patients subjected to the intensive therapy, the control category of systolic BP was changed from 11 to 37% in well-controlled cases, from 42 to 30% in poorly-controlled cases, from 39 to 26% in masked hypertension cases and from 8 to 7% in white-coat hypertension cases. The shift in categories in both poorly-controlled and masked hypertension cases to the better category (well-controlled), was statistically significant (p=0.001, by Wilcoxon's signed rank test). Similarly, the control category of diastolic BP was changed from 45 to 43% in well-controlled cases, from 13 to 15% in poorly-controlled cases, from 34 to 32% in masked hypertension cases and from 8 to 10% in white-coat hypertension cases. There was a tendency for the prevalence of poorly-controlled and masked hypertension to improve to the well-controlled category in response to intensive therapy (p=0.0625, by Wilcoxon's signed rank test). 3) The plasma concentration of plasminogen activator inhibitor (PAI-1)/tissue plasminogen activator (t-PA) complex (total PAI-1 complex) was significantly decreased after intensive therapy (17.3+/-7.8 ng/ml vs. 13.5+/-4.6 ng/ml, n=28, p<0.01 by paired t-test). In contrast, the plasma concentration of t-PA was unchanged even after intensive therapy (4.8+/-3.9 ng/ml vs. 6.2+/-2.9 ng/ml, n=28, ns). These data suggest that home BP obtained in the morning is a useful measure for evaluating morning hypertension in PD patients, most of whom have refractory hypertension categorized as either poorly-controlled or masked hypertension. Intensive treatment with ACE-I/ARB given in the evening along with alpha1-blocker at bed time combined with a diuretic and/or long-acting CCB in the morning is efficacious in controlling the BP of patients with refractory hypertension in PD patients. The link between the reduction in plasma total PAI-1 levels and the intensive therapy may suggest that this therapeutic strategy could prevent thrombotic events associated with morning hypertension in patients on PD.
...
PMID:[Antihypertensive therapy for refractory morning hypertension in patients on peritoneal dialysis]. 1575 62

Essential arterial hypertension often predisposes patients to prothrombotic state and increased risk of vascular and organ complications. Vital role in regulation of hemostatic processes is played by genetic factors, renin-angiotensin system and disorders of lipid metabolism. Prime genetic factors involved in the process are 4G/5G polymorphism of promoter region coding tissue plasminogen activator inhibitor-1 (PAI-1) and I/D polymorphism for angiotensin converting enzyme (ACE) gene. The aim of work was the evaluation of alterations within fibrinolysis system (estimation of t-PA and PAI-1 levels), fibrinogen concentration (Fb) and ACE activity with regard to co-existent dyslipidemia and features of left ventricle hypertrophy (LVH). Moreover the analysis of influence of 4G/5G PAI and I/D ACE gene polymorphism on intensification of aforementioned alterations among hypertensive patients was performed. Research was carried out in 170 subjects under 40 years old, in two study groups, HT-- hypertensive group--125 patients with previously untreated hypertension without clinical features of ischaemic heart disease and NT--45 normotensive, healthy subjects. HT group has been further divided into four subgroups: DLP (dyslipidemic, n = 51), NLP (normolipidemic n = 74), LVH+ (with features of left ventricle hypertrophy, n = 35), LVH (-) (without features of left ventricle hypertrophy, n = 90). In a whole HT group significantly higher levels of PAI-1, t-PA and Fb were noted in comparison to NT group, considerably more pronounced within DLP rather than NLP subgroups. Moreover, pronounced increase in ACE activity was recorded in DLP and LVH+ subgroups. It has been proved that 4G/4G homozygous subjects of 4G/5G PAI-1 gene polymorphism from HT group tend to present higher levels of PAI-1 and t-PA if contrasted to 4G/4G genotype of NT group, with more distinct effect within DLP subgroup. Carriers of D allele (genotypes I/D, D/D) of I/D ACE gene polymorphism from HT group characterise with significantly higher activity of ACE in contrast to I/I genotype of HT group, with particularly marked effect in DLP and LVH+ subgroups. Basing on above mentioned results it may be concluded that essential hypertension (especially if complicated with dyslipidemia) impairs fibrinolysis, what might be related to renin-angiotensin system activation in lipid metabolism disorders. Deletion alleles of 4G/5G polymorphism (4G allele) and I/D polymorphism (D allele) in patients with hypertension independently modify fibrinolysis towards prothrombotic state with more distinct effect in dyslipidemia. Increased activity of ACE in D allele carriers may predispose to left ventricle hypertrophy.
...
PMID:[Plasminogen activator inhibitor-1 (PAI-1) 4G/5G and angiotensin converting enzyme (ACE) I/D gene polymorphisms and fibrinolytic activity in patients with essential hypertension and dyslipidemia]. 1613 May 96

The Clinical Trials described in this article were presented at the Hotline and Clinical Trial Update Sessions of the European Society of Cardiology Congress held in September 2007 in Vienna, Austria. The sessions chosen for this article represent the scope of interest of Cardiovascular Drugs and Therapy. The presentations should be considered preliminary, as further analyses could alter the final publication of the results of these studies. PROSPECT evaluated echocardiographic criteria for optimal selection of patients with moderate to severe heart failure who may benefit from cardiac resynchronisation therapy, however concluded that no single echocardiographic measure can be recommended. EVEREST found that tolvaptan, a vasopressin V(2) antagonist, resulted in early weight reduction and improvement of dyspnoea in patients with acute heart failure, but lacked long term improvement. In ARISE, the anti-oxidant succinobucal did not affect the primary outcome in high risk cardiovascular patients, but improved the combination of cardiovascular death, myocardial infarction and stroke, and diabetic control in diabetics. ALOFT showed that the addition of the renin inhibitor aliskiren to an ACE inhibitor or ARB and a beta-blocker leads to favourable effects on neurohormonal actions in heart failure. FINESSE markedly improved coronary patency before PCI with half-dose reteplase/abciximab in STEMI patients, however without significantly improving short-term outcome. The Prague-8 Study evaluated whether routine clopidogrel administered >6 h pre-angiography would be a safe way to achieve therapeutic drug levels in case a follow-up intervention would be considered immediately, but appeared not justified because of bleeding complications. CARESS in MI showed that high risk patients with evolving STEMI who undergo thrombolytic therapy should undergo PCI early after the thrombolysis. Finally, the ACUITY trial found that in moderate or high risk Non ST elevation ACS patients triaged to PCI, coronary artery bypass graft (CABG) surgery, or medical management, bivalirudin, with or without associated GPIIb/IIIa inhibitor therapy, resulted in a marked reduction of bleeding at 30 days whilst preserving the ischemic and mortality benefit at 1 year follow up.
...
PMID:Clinical trials update from the European Society of Cardiology Congress in Vienna, 2007: PROSPECT, EVEREST, ARISE, ALOFT, FINESSE, Prague-8, CARESS in MI and ACUITY. 1799 67


<< Previous 1 2 3 4 5 6 Next >>