23 results on '"Renke Maas"'
Search Results
2. Stable isotope dilution assay for liquid chromatography–tandem mass spectrometric determination of l-homoarginine in human plasma
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Renke Maas, Edzard Schwedhelm, Rainer H. Böger, Dorothee Atzler, and Maren Mieth
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Carbon Isotopes ,Electrospray ,Chromatography ,Arginine transport ,Clinical Biochemistry ,Indicator Dilution Techniques ,Substrate (chemistry) ,Cell Biology ,General Medicine ,Tandem mass spectrometry ,Homoarginine ,Biochemistry ,Analytical Chemistry ,Nitric oxide ,Dilution ,Arginase ,chemistry.chemical_compound ,chemistry ,Tandem Mass Spectrometry ,Isotopes of carbon ,Humans ,Chromatography, Liquid - Abstract
Nitric oxide (NO), the endogenous modulator of vascular tone and structure, originates from oxidation of L-arginine catalysed by NO synthase (NOS). The L-arginine derivative L-homoarginine serves as an alternative NOS substrate releasing NO, competing with L-arginine for NOS, arginase, and arginine transport. In the present article we report a liquid chromatography-tandem mass spectrometric (LC-tandem MS) method for the determination of L-homoarginine in human plasma by stable-isotope dilution. L-[(13)C(6)]-Homoarginine was used as internal standard. This method provides high sample throughput of 25-μl aliquots of plasma with an analysis time of 4 min using LC-tandem MS electrospray ionisation in the positive mode (ESI+). Specific transitions for L-homoarginine and L-[(13)C(6)]-homoarginine were m/z 245 → m/z 211 and m/z 251 → m/z 217, respectively. The mean intra- and interassay CVs were 7.4 ± 4.5% (±SD) for 0.1-50 μmol/L and 7.5 ± 2.0% for 2 and 5 μmol/L, respectively. Applying this method, a mean plasma concentration of L-homoarginine of 2.5 ± 1.0 μmol/L was determined in 136 healthy humans.
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- 2011
3. Redox‐generated isoprostanes are associated with residual platelet activity in aspirin‐treated patients with stable coronary heart disease
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D. Tsikas, R. Trinks, Rainer H. Böger, Ghainsom D. Kom, Edzard Schwedhelm, A. Bierend, and Renke Maas
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Blood Platelets ,Male ,medicine.medical_specialty ,Isoprostane ,Coronary Disease ,Enzyme-Linked Immunosorbent Assay ,Isoprostanes ,medicine.disease_cause ,Gas Chromatography-Mass Spectrometry ,Excretion ,Pathogenesis ,chemistry.chemical_compound ,Tandem Mass Spectrometry ,Internal medicine ,Humans ,Medicine ,Platelet ,Platelet activation ,Aged ,Creatinine ,Aspirin ,Dose-Response Relationship, Drug ,business.industry ,Hematology ,Middle Aged ,Oxidative Stress ,Endocrinology ,chemistry ,Female ,business ,Oxidation-Reduction ,Platelet Aggregation Inhibitors ,Oxidative stress ,medicine.drug - Abstract
Summary. Aim: Insufficient platelet inhibition by low-dose aspirin is associated with poor prognosis in patients with coronary heart disease (CHD). We sought to investigate the prevalence of this phenomenon in patients with stable CHD and to study whether oxidative stress plays a role in its pathogenesis. Methods and results: We studied the platelet response to longterm (‡ 6 months) low-dose (100 mg per day) aspirin in 130 consecutive patients with stable CHD (age 66 ± 8 years, 83% male). Among a wide distribution of platelet responses to collagen, ADP, and arachidonic acid, the vast majority of patients in the highest tertile of residual platelet activity (defined as aspirin low-responders) were characterized by lack of platelet inhibition by aspirin in vitro, significantly although not completely suppressed platelet TXB2 production and COX-1 activity, and significantly higher urinary 8-iso-prostaglandin F2a excretion [186 (147–230) vs. 230 (188–318) pg per mg creatinine; median (IQR), P < 0.001; measured by GC-MS]. Conclusion: A relevant proportion of patients with CHD show insufficient platelet inhibition by low-dose aspirin. Oxidative stress and lipid peroxidation causing isoprostane formation may underlie inadequate platelet inhibition in an aspirininsensitive manner in patients with cardiovascular disease.
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- 2010
4. Dimethylarginine Dimethylaminohydrolase Overexpression Ameliorates Atherosclerosis in Apolipoprotein E-Deficient Mice by Lowering Asymmetric Dimethylarginine
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Dorothee Atzler, Juliane Heusinger-Ribeiro, Michaela Arend, Edzard Schwedhelm, Rainer H. Böger, Joachim Strobel, Nada Cordasic, Arthur J. Pope, Johannes Jacobi, Karl F. Hilgers, Arturo J. Cardounel, and Renke Maas
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Male ,Risk ,Apolipoprotein E ,Genetically modified mouse ,medicine.medical_specialty ,Arginine ,Transgene ,Blood Pressure ,Mice, Transgenic ,Biology ,Nitric Oxide ,Amidohydrolases ,Pathology and Forensic Medicine ,Nitric oxide ,Pathogenesis ,Mice ,chemistry.chemical_compound ,Apolipoproteins E ,Internal medicine ,medicine ,Animals ,Humans ,Aorta ,Models, Genetic ,Atherosclerosis ,Nitric oxide synthase ,Endocrinology ,chemistry ,Cardiovascular Diseases ,biology.protein ,Asymmetric dimethylarginine ,Regular Articles - Abstract
Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, is increasingly recognized as a novel biomarker in cardiovascular disease. To date, it remains unclear whether elevated ADMA levels are merely associated with cardiovascular risk or whether this molecule is of functional relevance in the pathogenesis of atherosclerotic vascular disease. To clarify this issue, we crossed dimethylarginine dimethylaminohydrolase (DDAH) transgenic mice that overexpress the human isoform 1 of the ADMA degrading enzyme DDAH into ApoE-deficient mice to generate ApoE(-/-)/hDDAH1(+/-) mice. In these mice, as well as ApoE(-/-) wild-type littermates, atherosclerosis within the aorta as well as vascular function of aortic ring preparations was assessed. We report here that overexpression of hDDAH1 reduces plaque formation in ApoE(-/-) mice by lowering ADMA. The extent of atherosclerosis closely correlated with plasma ADMA levels in male but not female mice fed either a standard rodent chow or an atherogenic diet. Functional analysis of aortic ring preparations revealed improved endothelial function in mice overexpressing hDDAH1. Our findings provide proof-of-principle that ADMA plays a causal role as a culprit molecule in atherosclerosis and support recent evidence indicating a functional relevance of DDAH enzymes in genetic mouse models. Together, these results demonstrate that pharmacological interventions targeting the ADMA/DDAH pathway may represent a novel approach in the prevention and management of cardiovascular diseases.
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- 2010
5. ADMA and the role of the genes: Lessons from genetically modified animals and human gene polymorphisms
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Rainer H. Böger, Nicole Lüneburg, and Renke Maas
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Pharmacology ,Genetics ,medicine.medical_specialty ,Polymorphism, Genetic ,Endogeny ,Biology ,Arginine ,medicine.disease ,Pathophysiology ,Nitric oxide ,Animals, Genetically Modified ,Nitric oxide synthase ,Disease Models, Animal ,chemistry.chemical_compound ,Endocrinology ,chemistry ,Fibrosis ,Polymorphism (computer science) ,Internal medicine ,medicine ,biology.protein ,Animals ,Humans ,Asymmetric dimethylarginine ,Gene - Abstract
In large population-based cohorts, elevated plasma levels of asymmetric dimethylarginine (ADMA) were found to be associated with cardiovascular events and mortality. Impairment of nitric oxide (NO) synthesis from l-arginine has been postulated as underlying mechanism. In the present review, we compare different experimental models of NOS deficiency or overexpression with corresponding models of altered metabolism of ADMA by dimethylarginine dimethylaminohydrolase (DDAH). The latter models show a considerable overlap with the pathophysiological features of impaired NO synthesis, such as impaired endothelial function, elevation of blood pressure, and microvascular fibrosis. In line with these findings, first data regarding genetic variation of DDAH-metabolism in humans are reminiscent of the (rather modest) effects previously observed with polymorphisms of the eNOS gene. However, several peculiar observations suggest that ADMA- or DDAH-related pathology may extend beyond impairment of NO-mediated signalling. Notably, the complete knock out of DDAH1 appears to be lethal while triple NOS(-/-) mice are viable. Moreover, some ADMA-mediated pathology appears to respond rather to ACE-inhibition than to l-arginine. Here, a further investigation of alternative target enzymes for ADMA and other endogenous DDAH substrates is warranted.Taken together, the current data suggest that ADMA-related pathology can largely but not completely be explained by impaired NO metabolism.
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- 2009
6. Extensive characterization of the human DDAH1 transgenic mice
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Dorothee Atzler, Christine Schmitz, Johannes Jacobi, Rainer H. Böger, Renke Maas, Eike Christin Von Leitner, Edzard Schwedhelm, Thomas Meinertz, Thomas Münzel, Stephan Baldus, John P. Cooke, and Karsten Sydow
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Male ,Genetically modified mouse ,medicine.medical_specialty ,Endothelium ,Arginine ,Transgene ,Mice, Transgenic ,Nitric Oxide ,Gene Expression Regulation, Enzymologic ,Amidohydrolases ,Mice ,chemistry.chemical_compound ,Enos ,Internal medicine ,medicine ,Animals ,Humans ,Tissue Distribution ,RNA, Messenger ,Pharmacology ,Kidney ,biology ,Chemistry ,Arteriosclerosis ,medicine.disease ,biology.organism_classification ,Isoenzymes ,Mice, Inbred C57BL ,medicine.anatomical_structure ,Endocrinology ,Organ Specificity ,Female ,Asymmetric dimethylarginine ,Signal Transduction - Abstract
Purpose of the research Overexpression of the human dimethylarginine dimethylaminohydrolase type 1 (hDDAH1) gene was reported to have beneficial cardiovascular effects in mice. To date, it is unclear whether these effects are related to enhanced metabolic clearance of asymmetric dimethylarginine (ADMA) and l - N G -mono-methyl- l -arginine ( l -NMMA) or increased DDAH1 expression and activity in cardiovascular tissues of hDDAH1 transgenic mice. Principal results DDAH activity (DDAH1 + DDAH2) was found to be markedly increased in aortic and heart tissues but unaltered in liver and kidney tissues of hDDAH1 transgenic as compared to wild-type (WT) mice. In WT mice, DDAH activity was more abundant in liver and kidney as compared to aorta and heart, suggesting a possible ceiling effect of activity which was unsurpassed by hDDAH1 overexpression. Major conclusions Overexpression of hDDAH1 in healthy mice does not result in an improved DDAH-metabolic capacity of kidney and liver under normal, i.e. unchallenged conditions. The most likely explanation for low ADMA and l -NMMA concentrations in hDDAH1 transgenic mice is a decreased release of ADMA from aorta, heart, and possibly other organs. The protective cardiovascular effects seen in these animals may therefore be related to an improved activity of the DDAH enzyme in the cardiovascular system and not be related to improved renal and hepatic clearance of ADMA and l -NMMA.
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- 2009
7. Plasma asymmetric dimethylarginine, l-arginine and left ventricular structure and function in a community-based sample
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Emelia J. Benjamin, Wolfgang Lieb, Vanessa Xanthakis, Friedrich Schulze, Rainer H. Böger, Ramachandran S. Vasan, Ralf A. Benndorf, Jayashri Aragam, Lisa M. Sullivan, Renke Maas, and Edzard Schwedhelm
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Male ,medicine.medical_specialty ,Arginine ,Offspring ,Heart Ventricles ,Population ,Risk Assessment ,Article ,Muscle hypertrophy ,Nitric oxide ,Ventricular Dysfunction, Left ,chemistry.chemical_compound ,Risk Factors ,Internal medicine ,medicine ,Humans ,Heart Atria ,Obesity ,education ,Aged ,Ultrasonography ,education.field_of_study ,Framingham Risk Score ,business.industry ,Middle Aged ,Myocardial Contraction ,Endocrinology ,chemistry ,Population Surveillance ,Multivariate Analysis ,Linear Models ,Biomarker (medicine) ,Female ,Cardiology and Cardiovascular Medicine ,Asymmetric dimethylarginine ,business - Abstract
Objective Increasing evidence indicates that cardiac structure and function are modulated by the nitric oxide (NO) system. Elevated plasma concentrations of asymmetric dimethylarginine (ADMA; a competitive inhibitor of NO synthase) have been reported in patients with end-stage renal disease. It is unclear if circulating ADMA and l-arginine levels are related to cardiac structure and function in the general population. Methods We related plasma ADMA and l-arginine (the amino acid precursor of NO) to echocardiographic left ventricular (LV) mass, left atrial (LA) size and fractional shortening (FS) using multivariable linear regression analyses in 1919 Framingham Offspring Study participants (mean age 57 years, 58% women). Results Overall, neither ADMA or l-arginine, nor their ratio was associated with LV mass, LA size and FS in multivariable models ( p >0.10 for all). However, we observed effect modification by obesity of the relations of ADMA and LA size ( p for interaction p =0.04): ADMA was positively related to LA size in obese individuals (adjusted- p =0.0004 for trend across ADMA quartiles) but not in non-obese people. Conclusion In our large community-based sample, plasma ADMA and l-arginine concentrations were not related to cardiac structure or function. The observation of positive relations of LA size and ADMA in obese individuals warrants confirmation.
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- 2009
8. Asymmetric dimethylarginine predicts outcome and time of stay in hospital in patients attending an internal medicine emergency room
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Renke Maas, Reinhold Muller, Martin Möckel, Christian Müller, Jörn O. Vollert, Friedrich Schulze, Edzard Schwedhelm, and Rainer H. Böger
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Adult ,Male ,Pediatrics ,medicine.medical_specialty ,Clinical Biochemistry ,Arginine ,Risk Assessment ,Biochemistry ,chemistry.chemical_compound ,Internal medicine ,medicine ,Clinical endpoint ,Humans ,Risk factor ,Aged ,Proportional Hazards Models ,business.industry ,Proportional hazards model ,Biochemistry (medical) ,Hazard ratio ,General Medicine ,Odds ratio ,Length of Stay ,Middle Aged ,Prognosis ,Logistic Models ,chemistry ,Quartile ,Cohort ,Female ,Emergency Service, Hospital ,Asymmetric dimethylarginine ,business - Abstract
Introduction: For patients attending the emergency room (ER) valid diagnostic criteria which identify patients at risk for an adverse outcome are needed. We investigated the predictive value of asymmetric dimethylarginine (ADMA) in unselected patients attending an internal medicine ER regarding outcome of the patients and duration of stay in the hospital. Patients and methods: Patients (n = 417) attending the ER were classified according to their primary diagnosis. Routine laboratory tests were performed and ADMA was determined. Patients were followed for a primary endpoint of in hospital death and complicated outcome. Results: ADMA levels were highest in patients with a cancer-related diagnosis (0.76 (0.63–0.93) µmol/L) and in patients with a cardiovascular diagnosis (0.69 (0.60–0.80) µmol/L; p < 0.001). Overall, we found increasing proportions of patients experiencing the primary end point over the quartiles of ADMA (4.6%, 8.2%, 9.6%, and 15.8%; p = 0.007). ADMA had the highest predictive value for the primary endpoint in patients with cardiovascular disease (odds ratio 19.4; p = 0.029). In a Cox proportional hazard model ADMA was an independent predictor of the length of hospitalization (hazard ratio 2.0 (95% CI: 1.3–3.3); p = 0.006) in the entire cohort. Conclusion: We conclude that ADMA independently predicts future complications and hospitalization in patients attending an ER.
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- 2009
9. Acute effects of various fast-food meals on vascular function and cardiovascular disease risk markers: the Hamburg Burger Trial
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Tanja K. Rudolph, Edzard Schwedhelm, Rainer H. Böger, Jing Tan-Andresen, Renke Maas, Ulrich Riederer, and Kaike Ruempler
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Adult ,Acute effects ,medicine.medical_specialty ,Restaurants ,Medicine (miscellaneous) ,Choice Behavior ,Food Preferences ,Animal science ,Risk Factors ,medicine.artery ,Internal medicine ,medicine ,Humans ,Single-Blind Method ,Brachial artery ,Aged ,Orange juice ,Meal ,Cross-Over Studies ,Nutrition and Dietetics ,Vascular disease ,French fries ,business.industry ,digestive, oral, and skin physiology ,Feeding Behavior ,Middle Aged ,medicine.disease ,Crossover study ,Vasodilation ,Postprandial ,Endocrinology ,Cardiovascular Diseases ,business ,Nutritive Value - Abstract
BACKGROUND High-fat meals have negative effects on endothelial function, but vitamin-rich side orders may prevent these negative effects. OBJECTIVE The acute effects of conventional and alternative fast-food meals on vascular function and various cardiovascular biomarkers were investigated. DESIGN In a crossover study, flow-mediated endothelium-dependent dilatation (FMD) and cardiovascular disease risk markers were investigated in 24 healthy volunteers before and 2 and 4 h after 3 fast-food meals: a conventional beef burger with French fries, ketchup, and carbonated lemon-flavored soda (meal 1); a vegetarian burger with French fries, ketchup, and carbonated lemon-flavored soda (meal 2); and a vegetarian burger with salad, fruit, yogurt, and orange juice (meal 3). RESULTS FMD decreased after all 3 fast-food meals: the values were 9.7 +/- 2.5%, 7.5 +/- 3.5%, and 6.2 +/- 3.3% for meal 1; 9.2 +/- 3.4%, 7.1 +/- 3.4%, and 6.3 +/- 4.0% for meal 2; and 8.8 +/- 3.3%, 6.2 +/- 4.0%, and 6.8 +/- 4.3% for meal 3 at baseline, 2 h, and 4 h, respectively. There were significant intraindividual differences for time (P < 0.001) but not for type of meal (P = 0.677). A postprandial increase in baseline diameter of the brachial artery was significant for time (P < 0.001) but not for type of meal (P = 0.148). CONCLUSIONS Against common expectations, a conventional beef burger meal and presumably healthier alternatives with or without vitamin-rich side orders did not differ significantly in their acute effects on vascular reactivity. The frequently reported postprandial decline in FMD may be attributed in part to a postprandial increase in baseline arterial diameter.
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- 2007
10. Asymmetric Dimethylarginine Determines the Improvement of Endothelium-Dependent Vasodilation by Simvastatin
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Anneke Bierend, Edzard Schwedhelm, Rainer H. Böger, Tanja K. Rudolph, Ralf A. Benndorf, Renke Maas, Gerhild I. Böger, and Ekaterina Dumbadze
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medicine.medical_specialty ,Arginine ,biology ,Endothelium ,business.industry ,C-reactive protein ,nutritional and metabolic diseases ,Vasodilation ,biology.organism_classification ,chemistry.chemical_compound ,Endocrinology ,medicine.anatomical_structure ,chemistry ,Enos ,Simvastatin ,Internal medicine ,HMG-CoA reductase ,medicine ,biology.protein ,Asymmetric dimethylarginine ,business ,Cardiology and Cardiovascular Medicine ,medicine.drug - Abstract
Objectives We hypothesized that the level of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of endothelial nitric oxide (NO) synthase (eNOS), might determine the endothelial effects of statins. Background Endothelial NO synthase is up-regulated by statins. However, statins failed to improve endothelial function in some studies. Asymmetric dimethylarginine inhibits eNOS by a mechanism that is reversible by L-arginine. Methods Ninety-eight clinically asymptomatic elderly subjects had their plasma ADMA levels screened. Those in the highest (high ADMA, n = 15) and lowest quartiles of the ADMA distribution (low ADMA, n = 13) were eligible to receive, in a randomized order, simvastatin (40 mg/day), L-arginine (3 g/day), or a combination of both, each for 3 weeks. Endothelium-dependent vasodilation (EDD) was assessed by brachial artery ultrasound. Results Simvastatin had no effect on EDD in subjects with high ADMA (6.2 ± 1.2% vs. 6.1 ± 0.9%), whereas simvastatin plus L-arginine significantly improved EDD (9.8 ± 1.5% vs. 5.3 ± 0.8%; p Conclusions Simvastatin does not enhance endothelial function in subjects with elevated ADMA, whereas it does so in patients with low ADMA. Combination of simvastatin with oral L-arginine improves endothelial function in subjects with high ADMA, but has no additional effect in subjects with low ADMA. As NO-mediated effects may play a major role in the therapeutic effects of statins, ADMA concentration is an important factor that influences the “pleiotropic” effects of simvastatin.
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- 2007
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11. Telmisartan improves insulin sensitivity in nondiabetic patients with essential hypertension
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Renke Maas, Elisabeth Silberhorn, Tanja K. Rudolph, Friedrich Schulze, Edzard Schwedhelm, Ralf A. Benndorf, Daniel Appel, and Rainer H. Böger
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Male ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Nisoldipine ,Angiotensin-Converting Enzyme Inhibitors ,Essential hypertension ,Benzoates ,Body Mass Index ,Cohort Studies ,Endocrinology ,Insulin resistance ,Internal medicine ,medicine ,Humans ,Telmisartan ,Antihypertensive Agents ,Aged ,Adiponectin ,business.industry ,Insulin ,Type 2 Diabetes Mellitus ,Middle Aged ,Calcium Channel Blockers ,medicine.disease ,PPAR gamma ,Hypertension ,Benzimidazoles ,Female ,Insulin Resistance ,Metabolic syndrome ,business ,Angiotensin II Type 1 Receptor Blockers ,medicine.drug - Abstract
Hypertension is a cardiovascular risk factor commonly associated with insulin resistance, the metabolic syndrome, and type 2 diabetes mellitus. Recent in vitro data indicate that certain angiotensin receptor antagonists, for example, telmisartan, activate peroxisome proliferator-activated receptor gamma (PPAR-gamma) and increase adiponectin protein content in adipocytes. By this means, they may improve insulin sensitivity in vivo. To investigate the effect of antihypertensive treatment on insulin sensitivity and fasting adiponectin serum levels, 37 nondiabetic patients with essential hypertension were randomized to receive telmisartan, the calcium channel blocker nisoldipine, or their combination for 6 weeks in a prospective, parallel group study. Fasting serum glucose, insulin, and adiponectin were evaluated before, 3 weeks (low dose), and 6 weeks (high dose) after initiation of treatment. Furthermore, the effect of telmisartan on PPAR-gamma receptor activity was investigated in vitro using a PPAR-gamma reporter gene assay. As reported previously, telmisartan significantly enhanced PPAR-gamma receptor activity in vitro. At baseline, a positive correlation between insulin serum levels and body mass index of investigated subjects was observed, whereas body mass index and serum adiponectin levels were negatively associated. High-dose treatment with telmisartan but not with nisoldipine reduced serum insulin levels as well as the homeostasis model assessment of insulin resistance, but did not affect serum adiponectin levels. In conclusion, in our study cohort of nondiabetic patients with essential hypertension, telmisartan improved insulin sensitivity by mechanisms apparently not involving adiponectin induction. Future studies will demonstrate whether these telmisartan-induced effects may contribute to a blood pressure-independent reduction in cardiovascular morbidity.
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- 2006
12. Asymmetric dimethlyarginine directly promotes chronic kidney disease progression: Evidence from a mendelian randomization approach in the GCKD study
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Maren Mieth, Stephanie Titze, Kai-Uwe Eckardt, Florian Kronenberg, Markus P. Schneider, Yong Li, and Renke Maas
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business.industry ,Mendelian randomization ,medicine ,Cardiology and Cardiovascular Medicine ,medicine.disease ,Bioinformatics ,business ,Kidney disease - Published
- 2016
13. Old and new cardiovascular risk factors: from unresolved issues to new opportunities
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Rainer H. Böger and Renke Maas
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Asymmetrical dimethylarginine ,medicine.medical_specialty ,business.industry ,Cardiovascular risk factors ,Cardiovascular research ,General Medicine ,Disease ,Causality ,Terminology ,Endocrinology ,Cardiovascular Diseases ,Risk Factors ,Internal medicine ,Risk IT ,Internal Medicine ,Humans ,Medicine ,Cardiology and Cardiovascular Medicine ,business ,Intensive care medicine ,Risk assessment - Abstract
With the aim of identifying areas that may deserve some further thinking the present review deliberately points out controversial issues in cardiovascular research and risk assessment. In the first part of the review general aspects are addressed regarding the evaluation of risk factors. A first point of concern is the frequent practice of combining different vascular events and effects in different vascular beds into a single endpoint. Furthermore, verification of vascular events in clinical reality may be surprisingly inaccurate. Problems in risk assessment also arise from overlapping properties (shared pathophysiological pathways) of traditional risk factors like hypertension, obesity and diabetes. In the second part of the review unresolved issues concerning selected established and emerging risk factors are discussed. The difficulty of establishing causality in cardiovascular disease is addressed, using modification of LDL cholesterol and accumulating evidence for pleiotropic effects of the LDL cholesterol-lowering statins as an example. As an alternative or supplement to the notion of LDL-related cardiovascular risk it is proposed to distinguish between statin-sensitive and statin-insensitive cardiovascular risk. Finally the future prospects of selected new and emerging risk factors like CRP, homocysteine, asymmetrical dimethylarginine (ADMA), oxLDL, and isoprostanes are evaluated. In summary, imprecise terminology and varying definitions of "cardiovascular risk" may lead to a considerable blurring of our current risk estimates, which may also explain some presently controversial issues. With several new risk factors and substantial changes in lifestyle and treatment patterns on the horizon major changes in the hierarchy of risk factors may be inevitable.
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- 2003
14. Left ventricular hypertrophy, cardiac remodeling and asymmetric dimethylarginine (ADMA) in hemodialysis patients
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Carmine Zoccali, Francesca Mallamaci, Renke Maas, Francesco A. Benedetto, Giovanni Tripepi, Lorenzo S. Malatino, Alessandro Cataliotti, Ignazio Bellanuova, Rainer Böger, and null on behalf of The Creed Investigators
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Adult ,Male ,medicine.medical_specialty ,Endothelium ,medicine.medical_treatment ,Arginine ,Nitric Oxide ,Left ventricular hypertrophy ,Muscle hypertrophy ,Ventricular Dysfunction, Left ,chemistry.chemical_compound ,uremia ,Renal Dialysis ,Internal medicine ,medicine ,Humans ,risk ,Aged ,Ejection fraction ,business.industry ,cardiovascular ,systolic dysfunction ,Middle Aged ,medicine.disease ,Dimethylargininase ,Uremia ,ADMA ,Vasodilation ,LVH ,Endocrinology ,medicine.anatomical_structure ,chemistry ,Echocardiography ,Nephrology ,Multivariate Analysis ,Cardiology ,dialysis ,Kidney Failure, Chronic ,Female ,Hypertrophy, Left Ventricular ,Endothelium, Vascular ,Hemodialysis ,business ,Asymmetric dimethylarginine - Abstract
Left ventricular hypertrophy, cardiac remodeling and asymmetric dimethylarginine (ADMA) in hemodialysis patients.BackgroundThe endogenous inhibitor of nitric oxide (NO), asymmetric dimethylarginine (ADMA), is a strong predictor of adverse cardiovascular outcomes in patients with end-stage renal disease (ESRD).MethodsSince arterial and cardiac remodeling is associated with altered endothelial microcirculatory responses to forearm ischemia (a NO-dependent response), interference of ADMA with the NO system may be important for the pathogenesis of left ventricular hypertrophy (LVH) in these patients. This study sought to identify the relationship between plasma ADMA and LV geometry and function in a cohort of 198 hemodialysis patients.ResultsPlasma ADMA was significantly higher (P = 0.008) in patients with LVH (median 3.00 μmol/L, inter-quartile range 1.73 to 3.97 μmol/L) than in those without this alteration (1.88 μmol/L, 1.15 to 3.56 μmol/L) and was significantly related to left ventricular (LV) mass (r = 0.26, P < 0.001). Interestingly, ADMA was much higher (P < 0.001) in patients with concentric LVH (3.60 μmol/L, 2.90 to 4.33 μmol/L) than in patients with eccentric LVH (2.17 μmol/L, 1.47 to 3.24 μmol/L) or normal LV mass (1.76 μmol/L, 1.13 to 2.65 μmol/L). Furthermore, plasma ADMA was higher (P = 0.02) in patients with systolic dysfunction (3.52 μmol/L, 2.08 to 5.87 μmol/L) than in those with normal LV function (2.58 μmol/L, 1.53 to 3.84 μmol/L) and inversely related to ejection fraction (EF; r = -0.25, P < 0.001). The link between ADMA and LV mass and EF was confirmed by multivariate analysis (ADMA vs. LVMI, β = 0.17, P = 0.006; ADMA vs. EF, β = -0.24, P < 0.001).ConclusionsOverall, this study indicates that raised plasma concentration of ADMA is associated to concentric LVH and LV dysfunction. Intervention studies are needed to see whether the link between ADMA and concentric LVH remodeling and LV dysfunction is a causal one.
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- 2002
15. Potentially Inappropriate Medication in the Elderly – Relevance and Economics of the 30 Top-Selling Priscus Agents in Germany
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Florian Meier, Martin Emmert, Renke Maas, Oliver Schöffski, and Katharina Pohl-Dernick
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Pediatrics ,medicine.medical_specialty ,business.industry ,Health Policy ,Public Health, Environmental and Occupational Health ,medicine ,Relevance (information retrieval) ,Marketing ,business - Published
- 2014
16. 875-3 Suppression of paroxysmal atrial tachyarrhythmias: Results of the SOPAT trial
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Frank Sonntag, Monica Patten, Renke Maas, Robert Hatala, Thomas Meinertz, Mirosław Dłużniewski, Bernd Lüderitz, and Grzegorz Opolski
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medicine.medical_specialty ,congenital, hereditary, and neonatal diseases and abnormalities ,business.industry ,Internal medicine ,medicine ,Cardiology ,cardiovascular system ,pathological conditions, signs and symptoms ,macromolecular substances ,cardiovascular diseases ,business ,Cardiology and Cardiovascular Medicine - Published
- 2004
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17. P174 ADMA (ASYMMETRIC DIMETHYLARGININE) PREDICTS ALL-CAUSE MORTALITY AND CARDIOVASCULAR EVENTS IN PATIENTS WITH PERIPHERAL ARTERIAL DISEASE: THE GETABI STUDY
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Heinz G. Endres, Rainer H. Böger, Ulrich Thiem, Ralf A. Benndorf, Nicole Lüneburg, Maike Anderssohn, Edzard Schwedhelm, B. von Stritzky, Dorothee Atzler, Curt Diehm, Renke Maas, and Harald Darius
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medicine.medical_specialty ,Arterial disease ,business.industry ,General Medicine ,Peripheral ,chemistry.chemical_compound ,chemistry ,Internal medicine ,Internal Medicine ,Cardiology ,medicine ,In patient ,Cardiology and Cardiovascular Medicine ,Asymmetric dimethylarginine ,business ,All cause mortality - Published
- 2010
18. O64. The regulation of NO synthesis by ADMA and DDAH—A promising therapeutic target?
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Renke Maas
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Cancer Research ,Physiology ,Clinical Biochemistry ,Biochemistry - Published
- 2008
19. PP177—Inhibitory Interaction of 125 Drugs with the Renally Expressed Organic Cation Transporter OCT2: Development of a Chemoinformatics-Based Model to Predict Transporter Inhibition in Silico
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Renke Maas, K. Münch, L. Terfloth, Martin F. Fromm, J. Schwöbel, and Oliver Zolk
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Pharmacology ,Organic cation transport proteins ,biology ,Cheminformatics ,business.industry ,In silico ,biology.protein ,Medicine ,Pharmacology (medical) ,Transporter ,business ,Inhibitory postsynaptic potential - Published
- 2013
20. O85. Polymorphisms in the promoter region of the dimethylarginine dimethylaminohydrolase 2 gene are associated with prevalence of hypertension
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Joachim Weil, Wolfgang Lieb, Christa Meisinger, Rainer H. Böger, Edzard Schwedhelm, Renke Maas, Jeanette Erdmann, Annette Peters, Nicole Lueneburg, Heribert Schunkert, and Jan Stritzke
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Genetics ,Cancer Research ,Dimethylarginine dimethylaminohydrolase ,Physiology ,Clinical Biochemistry ,Promoter ,Biology ,Biochemistry ,Gene - Published
- 2008
21. PO23-768 ASYMMETRIC DIMETHYLARGININE (ADMA) DETERMINES THE RESPONSIVENESS OF ENDOTHELIAL FUNCTION TO SIMVASTATIN TREATMENT — RESULTS OF A RANDOMIZED, CONTROLLED STUDY
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Renke Maas, T.K. Rudolph, G.I. Boger, E. Schwedhelm, and Rainer H. Böger
- Subjects
business.industry ,General Medicine ,Treatment results ,Pharmacology ,law.invention ,chemistry.chemical_compound ,chemistry ,Randomized controlled trial ,Simvastatin ,law ,Internal Medicine ,medicine ,Cardiology and Cardiovascular Medicine ,Asymmetric dimethylarginine ,business ,Function (biology) ,medicine.drug - Published
- 2007
22. PO15-399 CIGARETTE SMOKING LOWERS ASYMMETRIC DIMETHYLARGININE (ADMA) LEVELS – INFLUENCE OF DIMETHYLARGININE DIMETHYLAMINOHYDROLASE (DDAH)
- Author
-
Rainer H. Böger, F. Schulze, Renke Maas, K. Hamraz, and E. Schwedhelm
- Subjects
medicine.medical_specialty ,business.industry ,General Medicine ,chemistry.chemical_compound ,Dimethylarginine dimethylaminohydrolase ,Endocrinology ,chemistry ,Cigarette smoking ,Internal medicine ,Internal Medicine ,medicine ,Cardiology and Cardiovascular Medicine ,Asymmetric dimethylarginine ,business - Published
- 2007
23. Comparison of HPLC method and commercial ELISA assay for asymmetric dimethylarginine (ADMA) determination in human serum
- Author
-
Renke Maas, Friedrich Schulze, Rainer H. Böger, and Edzard Schwedhelm
- Subjects
chemistry.chemical_compound ,Chromatography ,Chemistry ,Clinical Biochemistry ,Cell Biology ,General Medicine ,Elisa assay ,Hplc method ,Asymmetric dimethylarginine ,Biochemistry ,Analytical Chemistry - Published
- 2006
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