Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Our group demonstrated recently that arginase I inhibition reduces endothelial dysfunction and blood pressure rising in spontaneously hypertensive rats [C. Demougeot, A. Prigent-Tessier, C. Marie, A. Berthelot, J. Hypertens. 23 (2005) 971; C. Demougeot, A. Prigent-Tessier, T. Bagnost, C. Andre, Y. Guillaume, M. Bouhaddi, C. Marie, A. Berthelot, Life Sci. 80 (2007) 1128]. This discovery opens interesting perspectives in the development of new drugs against hypertension. As well, in a previous paper [T. Bagnost, Y.C. Guillaume, M. Thomassin, J.F. Robert, A. Berthelot, A. Xicluna, C. Andre, J. Chromatogr. B: Analyt. Technol. Biomed. Life Sci. 856 (2007) 113], a novel biochromatographic column was developed in our laboratory for studying the binding of N(omega)-hydroxy-nor-l-arginine (nor-NOHA), an arginase inhibitor, with this enzyme. In this manuscript, using this novel biochromatographic concept, the effect of magnesium chloride on the nor-NOHA/arginase binding was analyzed for the first time. This study demonstrated that the salt ions interacted with arginase and played a great role in the nor-NOHA/arginase association. For a salt concentration (x) in the medium less than 3mM, the nor-NOHA/arginase binding decreased with x due to a decrease of the charge-charge interactions between nor-NOHA and its arginase binding site. Above 3mM of salt in the medium, the affinity of nor-NOHA to arginase increased slightly with x because the net number of ions (n) (Mg(2+) or Cl(-)) released or bound upon complex formation is low. As well, it was clearly demonstrated, that above 3 mM the n value depend on the salt concentration in the bulk solvent and was approximately nil for x=12 mM. This dependence was due to a gradual and conformational change of the arginase enzyme which around 12 mM adopted a less flexible structure; its binding site was thus less accessible to nor-NOHA and nor-NOHA-arginase association decreased slightly.
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PMID:Biochromatographic framework for analyzing magnesium chloride salt dependence on nor-NOHA binding to arginase enzyme. 1872 9

Although smoking and hypertension are classic risk factors for atherothrombotic diseases, the relationship of dyslipidemia and vascular diseases, other than myocardial infarction, is less clearly established, especially in young subjects. In the current study, a detailed analysis of the lipid and apolipoprotein profiles was conducted in young patients of ischemic cerebral stroke (IS) and peripheral arterial disease (PAD). Plasma levels of C-reactive protein (hs-CRP), total cholesterol (TC), high-density lipoprotein cholesterol (HDLc), low-density lipoprotein cholesterol (LDLc), triglycerides (TG), and apolipoproteins A-I (ApoA-I) and apolipoproteins B (ApoB), which include the ApoB/ApoA-I ratio, were analyzed in a group of 81 patients who presented with IS (n = 46) or PAD (n = 35) as well as in 167 control subjects. Significant differences were observed for hs-CRP, TC, HDLc, LDLc, TG, ApoA-I, and ApoB levels, as well as for the ApoB/ApoA-I ratio, between the control and the IS or PAD groups. However, after adjustment for sex, age, smoking, hypertension, hs-CRP, and dyslipidemia (LDLc, TC, HDLc, TG, ApoA, ApoB, and ApoB/ApoA-I ratio), hs-CRP, ApoB, and the ApoB/ApoA-I ratio were independently associated with increased risks of IS or PAD. Increased ApoB/ApoA-I ratio and hs-CRP levels are independently associated with occurrence of IS and PAD in young patients and are significant markers of alterations on lipid and apolipoproteic profiles and inflammatory responses, respectively, in these patients.
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PMID:ApoB/ApoA-I ratio in young patients with ischemic cerebral stroke or peripheral arterial disease. 1877 40

Secondary pulmonary hypertension (PH) is emerging as one of the leading causes of mortality and morbidity in patients with hemolytic anemias such as sickle cell disease (SCD) and thalassemia. Impaired nitric oxide (NO) bioavailability represents the central feature of endothelial dysfunction, and is a major factor in the pathophysiology of PH. Inactivation of NO correlates with hemolytic rate and is associated with the erythrocyte release of cell-free hemoglobin, which consumes NO directly, and the simultaneous release of the arginine-metabolizing enzyme arginase, which limits bioavailability of the NO synthase substrate arginine during the process of intravascular hemolysis. Rapid consumption of NO is accelerated by oxygen radicals that exists in both SCD and thalassemia. A dysregulation of arginine metabolism contributes to endothelial dysfunction and PH in SCD, and is strongly associated with prospective patient mortality. The central mechanism responsible for this metabolic disorder is enhanced arginine turnover, occurring secondary to enhanced plasma arginase activity. This is consistent with a growing appreciation of the role of excessive arginase activity in human diseases, including asthma and pulmonary arterial hypertension. New treatments aimed at improving arginine and NO bioavailability through arginase inhibition, suppression of hemolytic rate, oral arginine supplementation, or use of NO donors represent potential therapeutic strategies for this common pulmonary complication of hemolytic disorders.
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PMID:Nitric oxide and arginine dysregulation: a novel pathway to pulmonary hypertension in hemolytic disorders. 1899 48

Our group demonstrated that arginase inhibition reduces endothelial dysfunction in spontaneously hypertensive rats [C. Demougeot, A. Prigent-Tessier, C. Marie, A. Berthelot, J. Hypertens. 23 (2005) 971; C. Demougeot, A. Prigent-Tessier, T. Bagnost, C. Andre, Y. Guillaume, M. Bouhaddi, C. Marie, A. Berthelot, Life Sci. 80 (2007) 1128] which opens perspectives in the development of drugs against hypertension. In previous papers [T. Bagnost, Y.C. Guillaume, M. Thomassin, J.F. Robert, A. Berthelot, A. Xicluna, C. Andre, J. Chromatogr. B: Analyt. Technol. Biomed. Life Sci. 856 (2007) 113; T. Bagnost, Y.C. Guillaume, M. Thomassin, A. Berthelot, C. Demougeot, C. Andre, J. Chromatogr. B: Analyt. Technol. Biomed. Life Sci. 873 (2008) 37], we developed a biochromatographic column for studying the binding of an arginase inhibitor with this enzyme and the effect of magnesium on this binding. In this paper, the interaction of arginase inhibitors with an immobilized artificial membrane (IAM) has been studied using a biochromatographic approach. This IAM provided a biophysical model system to study the inhibitor passive transport across cells. It was demonstrated that more the inhibitor cross the cell membrane by passive diffusion more it is potent. As well, an analysis of the thermodynamics of the interaction of the arginase inhibitors with the IAM showed that van der Waals, hydrogen and ionic bonds were the main forces between the arginase inhibitors and the polar head groups of the IAM surface.
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PMID:A molecular chromatographic approach to analyze the cell diffusion of arginase inhibitors. 1937 85

1. Systemic arterial hypertension (SAH) is a major independent risk factor for cardiovascular disease. The physiopathology of SAH is multifactorial, complex and remains to be elucidated. Nitric oxide (NO) is an important regulator of vascular and haemostatic functions. The cationic amino acid l-arginine serves as the substrate for NO synthases (NOS) and arginase, an enzyme of the urea cycle. We have previously reported inhibition of l-arginine transport in erythrocytes and platelets in hypertension. 2. The aim of the present study was to investigate the l-arginine-NO pathway and urea cycle in platelets and their role in platelet function and systemic inflammatory responses in SAH patients. The expression and activity of NOS and arginase in platelets, platelet aggregation and plasma levels of C-reactive protein (CRP) were evaluated in 20 SAH patients and 18 age-matched healthy volunteers. 3. There was a reduction of NOS activity in hypertensive patients that was associated with activation of platelet aggregability induced by collagen, but not by ADP. Platelets from SAH patients exhibited compensatory overexpression of inducible NOS, but not endothelial NOS. Intraplatelet arginase activity in SAH patients was not affected, but systemic concentrations of CRP were increased compared with controls. 4. It is likely that diminished NO bioavailability in SAH contributes to cardiovascular complications. Our findings may provide the basis for developing new therapeutic approaches for the treatment of hypertension.
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PMID:Platelet aggregation in arterial hypertension: is there a nitric oxide-urea connection? 1956 24

Preeclampsia is characterized by vascular endothelial dysfunction partly attributed to oxidative stress. In the vasculature of preeclamptic women, we have shown increased lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) and arginase expression, which can contribute to vascular oxidative stress. However, the mechanisms of such upregulation are unknown. Methylglyoxal (MG) that plays a role in the vascular complications of diabetes mellitus and the development of hypertension can be one potential factor that can affect LOX-1 and arginase through its ability to induce oxidative stress in vascular cells. MG also reacts with lysine residues in proteins to generate advanced glycation end product, N(epsilon)-carboxy ethyl lysine, which also serves as a marker of MG. We hypothesized that markers of MG formation will be increased in the vasculature of preeclamptic women and that exogenous MG will induce oxidative stress by the upregulation of LOX-1 via arginase. We observed increased N(epsilon)-carboxy ethyl lysine expression in the vasculature of women with preeclampsia in comparison with normotensive pregnant women. Moreover, glyoxalase I and II, enzymes that detoxify MG, and glutathione reductase, which generates reduced glutathione, a cofactor for glyoxalase, are also reduced in preeclampsia. In cultured endothelial cells, MG increased arginase expression by 6 hours and LOX-1 expression by 24 hours. Inhibition of arginase or NO synthase significantly reduced MG-induced LOX-1 expression, superoxide levels, and nitrotyrosine staining. In conclusion, MG-induced LOX-1 expression is mediated via arginase upregulation likely because of uncoupling of NO synthase, which may have implications in preeclampsia.
Hypertension 2009 Oct
PMID:Evidence for increased methylglyoxal in the vasculature of women with preeclampsia: role in upregulation of LOX-1 and arginase. 1968 46

There is a growing evidence that arginase has a role in the pathophysiology of cardiovascular diseases including hypertension. We recently reported arginase upregulation in aortas from hypertensive spontaneously hypertensive rats (SHRs). The aim of this study was to determine whether arginase abnormalities occur in other tissues of SHR, including the target organs of hypertension. Experiments were conducted on 5-, 10-, 19- and 26-week-old SHRs and Wistar-Kyoto (WKY) rats. Arginase activity and expression were evaluated in heart, kidney, liver, lung and brain tissue extracts. To investigate the role of blood pressure by itself in arginase abnormalities, arginase activity was determined in 10-week-old SHRs previously treated with hydralazine (20 mg kg(-1) per day, for 5 weeks). Compared with WKY rats, cardiac arginase activity was higher in hypertensive SHRs aged 10 weeks (+46%, P<0.05), 19 weeks (+29%, P<0.05) and 26 weeks (+23%, NS). Similar results were found in lungs in which arginase activity was increased in SHRs aged 10 weeks (+39%, P<0.05), 19 weeks (+49%, P<0.05) and 26 weeks (+36%, P<0.05) compared with WKY rats. The changes in arginase activity in these tissues were not associated with changes in enzyme expression. The prevention of hypertension by hydralazine blunted the increase in arginase activity in the hearts but not in the lungs. No change in arginase activity/expression was found in the kidney, liver or brain. In conclusion, this study shows that increased arginase activity is not restricted to large vessels in SHRs and suggests that cardiac arginase activity is hemodynamic sensitive.
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PMID:Misregulation of the arginase pathway in tissues of spontaneously hypertensive rats. 1976 31

Vascular remodeling and smooth muscle cell proliferation are hallmark pathogenic features of pulmonary artery hypertension (PAH). Alterations in the metabolism of l-arginine via arginase and nitric oxide synthase play a critical role in the endothelial dysfunction seen in PAH. l-arginine metabolism by arginase produces l-ornithine and urea. l-ornithine is a precursor for polyamine and proline synthesis, ultimately leading to an increase in cellular proliferation. Given the integral role of the smooth muscle layer in the pathogenesis of hypoxia-induced PAH, we hypothesized that hypoxia would increase cellular proliferation via arginase induction in human pulmonary artery smooth muscle cells (hPASMC). We found that arginase II mRNA and protein expression were significantly increased in cultured hPASMC exposed to 1% O(2) for 24 and 48 h, which coincided with an increase in arginase activity at 48 h. There were no hypoxia-induced changes in levels of arginase I mRNA or protein in cultured hPASMC. Exposure to hypoxia resulted in more than one and a half times as many viable cells after 120 h than normoxic exposure. The addition of the arginase inhibitor, S-(2-boronoethyl)-l-cysteine, completely prevented both the hypoxia-induced increase in arginase activity and proliferation in hPASMC. Furthermore, transfection of small interfering RNA (siRNA) targeting arginase II in hPASMC resulted in knockdown of arginase II protein levels and complete prevention of the hypoxia-induced cellular proliferation. These data support our hypothesis that hypoxia increases proliferation of hPASMC through the induction of arginase II.
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PMID:Hypoxia promotes human pulmonary artery smooth muscle cell proliferation through induction of arginase. 1980 51

Knowledge obtained from the Turkish Adult Risk Factor (TARF) study on higher morbidity and mortality rates compared to other populations from coronary heart disease (CHD) among Turkish adults has been confirmed recently with greater power. This review provides insight that the dysfunctions of the protective serum proteins, attaining pro-inflammatory and atherogenic features, may be attributed to atherogenic dyslipidemia, oxidative stress, and systemic inflammation associated with the high prevalence of metabolic syndrome (MetS) among Turks. The mentioned protective protein dysfunctions, firstly described in a general population to date, are high-density lipoprotein (HDL), apolipoprotein (apo) A-I, A-II, and apoC-III, apart from adiponectin. Based on published findings of the TARF study, this review discusses the role of inflammatory mediators such as elevated C-reactive protein (CRP), apoB, apoC-III, fibrinogen, and low adiponectin serum levels in cardiometabolic risk comprising MetS, type 2 diabetes, and CHD, the degree of independence of these mediators from the ATP-III-defined MetS, and the influence of sex. Moreover, it is emphasized that dysfunctions of adiponectin and protective proteins related to HDL particles increase not only cardiometabolic risk significantly but also CHD risk among half of Turkish adults in a magnitude similar to or greater than that associated with traditional risk factors. Also underlined is the observation that cigarette smoking reduces the risk in Turkish women for the development of hypertension, MetS, and diabetes by mediation of positive effects on dysfunctional apoA-I, visceral fat accumulation and, above all, CRP levels. This knowledge is of utmost importance and sheds light to authorities and those concerned on the necessity of urgent and radical modifications regarding strategies in prevention and management of cardiovascular health of middle-aged Turks.
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PMID:[Major influence of dysfunctions of protective serum proteins on cardiometabolic risk among Turks and gender difference]. 2001 60

Pulmonary hypertension (PH) is a common complication of haemolytic anaemia. Intravascular haemolysis leads to nitric oxide (NO) depletion, endothelial and smooth muscle dysregulation, and vasculopathy, characterized by progressive hypertension. PH has been reported in patients with paroxysmal nocturnal haemoglobinuria (PNH), a life-threatening haemolytic disease. We explored the relationship between haemolysis, systemic NO, arginine catabolism and measures of PH in 73 PNH patients enrolled in the placebo-controlled TRIUMPH (Transfusion Reduction Efficacy and Safety Clinical Investigation Using Eculizumab in Paroxysmal Nocturnal Haemoglobinuria) study. At baseline, intravascular haemolysis was associated with elevated NO consumption (P < 0.0001) and arginase-1 release (P < 0.0001). Almost half of the patients in the trial had elevated levels (> or =160 pg/ml) of N-terminal pro-brain natriuretic peptide (NT-proBNP), a marker of pulmonary vascular resistance and right ventricular dysfunction previously shown to indicate PH. Eculizumab treatment significantly reduced haemolysis (P < 0.001), NO depletion (P < 0.001), vasomotor tone (P < 0.05), dyspnoea (P = 0.006) and resulted in a 50% reduction in the proportion of patients with elevated NT-proBNP (P < 0.001) within 2 weeks of treatment. Importantly, the significant improvements in dyspnoea and NT-proBNP levels occurred without significant changes in anaemia. These data demonstrated that intravascular haemolysis in PNH produces a state of NO catabolism leading to signs of PH, including elevated NT pro-BNP and dyspnoea that are significantly improved by treatment with eculizumab.
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PMID:Effect of eculizumab on haemolysis-associated nitric oxide depletion, dyspnoea, and measures of pulmonary hypertension in patients with paroxysmal nocturnal haemoglobinuria. 2023 Apr 3


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