ADMA Levels Research Articles

Protein arginine methylation of SERBP1 by protein arginine methyltransferase 1 affects cytoplasmic/nuclear distribution

Protein arginine methylation regulates a broad array of cellular processes. SERBP1 implicated in tumor progression through its putative involvement in the plaminogen activator protease cascade, is an RNA-binding protein containing an RG-rich domain and an RGG box domain that might be methylated by protein arginine N-methyltransferases (PRMTs). Asymmetric dimethylarginine (aDMA) was detected in SERBP1 and an indirect methyltransferase inhibitor adenosine dialdehyde (AdOx) significantly reduced the methylation signals. Arginines in the middle RG and C-terminal RGG region of SERBP1 are methylated based on the analyses of different deletion constructs. The predominant type I protein arginine methyltransferase PRMT1 co-immunoprecipitated with SERBP1 and the level of bound PRMT1 decreased upon the addition of AdOx. Recombinant PRMT1 methylated SERBP1 and knockdown of PRMT1 significantly reduced the aDMA level of SERBP1, indicating that SERBP1 is specifically methylated by PRMT1. Immunofluorescent analyses of endogenous SERBP1 showed predominant cytoplasmic localization of SERBP1. Treatment of AdOx or PRMT1 siRNA increased the nuclear localization of SERBP1. Analyses of different deletions indicated that the middle RG region is important for the nuclear localization while both N- and C- terminus are required for nuclear export. Low methylation of the C-terminal RGG region also favors nuclear localization. In conclusion, the RG-rich and RGG box of SERBP1 is asymmetrically dimethylated by PRMT1 and the modification affects protein interaction and intracellular localization of the protein. These findings provide the basis for dissecting the roles of SERBP1.

Modulation of nitric oxide synthase by arginase and methylated arginines during the acute phase of experimental multiple sclerosis

We explore the nitric oxide synthase modulation by methylated arginines, asymmetric (ADMA) and symmetric (SDMA) dimethyl-l-arginine and arginase, in early phase of experimental autoimmune encephalomyelitis (EAE), the most frequently used animal model for studying the multiple sclerosis (MS), during the treatment with selective inducibile nitric oxide synthase inhibitor — aminoguanidine (AG) and oxidative scavenger N-acetyl-l-cysteine (NAC), compared to the clinical signs, continual to our previous research.The given results showed that the arginase activity was significantly increased in EAE rats compared to the healthy and AG treated EAE animals (p<0.05), and it was significantly decreased compared to the NAC treated EAE animals (p<0.05) in examined tissues. The ADMA and SDMA levels were significantly decreased in EAE untreated animals compared to the AG and NAC treated EAE animals (p<0.05). As we have reported in our previous papers, nitric oxide (NO) production, was significantly increased in examined tissues of EAE rats compared to the control group (p<0.05). In AG and NAC treated EAE group NO production was decreased in all tissues compared to untreated EAE animals (p<0.05). Also, the AG and NAC treatment of EAE rats during the development of the disease, significantly decreased the clinical score of EAE treated animals compared to EAE group.Arginase and methylated arginine derivatives, involving also NO, appear to be essential modulators of the inflammatory response in acute phase of MS. The continued research of these findings may provide a new area in the treatment of multiple sclerosis acute phase.

Development of an Enzyme-Linked Immunosorbent Assay System for the Determination of Asymmetric Dimethylarginine Using a Specific Monoclonal Antibody

We produced a monoclonal antibody (mAb) against N(G),N(G)-dimethyl-L-arginine (asymmetric dimethylarginine: ADMA), an endogenous competitive inhibitor of nitric oxide synthase (NOS), and developed an enzyme-linked immunosorbent assay (ELISA). The competitive ELISA method using the mAb determined 5 nM-100 nM ADMA, and ADMA levels in human plasma and urine were found to be 0.78 µM and 51.3 µmol/g of creatinine respectively.

Regulation of Nitric Oxide by Cigarette Smoke in Airway Cells

Background and Objectives: Exhaled nitric oxide (NO) is decreased by smoking while oxides of nitrogen such as nitrites/nitrates (NOx) are increased. It was hypothesised that in vitro cigarette smoke extract (CSE) would either inhibit NO generation by increasing the NO synthase inhibitor, NG, NG-dimethyl-L-arginine (ADMA) or increase NOx levels via an oxidation pathway, which in turn could be inhibited by the antioxidant N-acetylcysteine NAC. Methods: Transformed airway cells (A549) were cultured with control medium, 1.0% CSE in culture medium, or 0.8 mM NAC with 1.0% CSE. Baseline L-arginine, NOx and ADMA levels were measured in the media. Conditioned media were then sampled at 1hour, 6 hours, 24 hours, 48 hours and 72 hours after incubation. Results: CSE induced significantly higher NOx levels (mean (SD) peak increase of 135.8 (126.6)% after incubation for 6 hours (p x which was partially reversed by NAC pre-treatment. ADMA levels were also increased after CSE exposure, suggesting that it activates the NO pathway via oxidative-stress while inhibition probably occurs via both ADMA and NOS.

ADMA, SDMA and L-arginine/ADMA Ratio but not DDAH Genetic Polymorphisms are Reliable Predictors of Diabetic Nephropathy Progression as Identified by Competing Risk Analysis

Background/Aims: Complex interplay of genetic and (patho)physiological factors influence availability of nitric oxide during the development and progression of diabetic complications. We assessed predictive value of commonly studied methylated asymmetric and symmetric dimethylarginines (ADMA and SDMA) and selected single nucleotide polymorphisms (SNPs) in dimethylarginine dimethylaminohydrolase (DDAH) 1 and 2 genes for the progression of diabetic nephropathy (DN). Methods: A total of 341 type 1 and type 2 diabetes patients with variable degree of kidney disease were included at baseline. Plasma levels of ADMA, SDMA and L-arginine were measured and six tagging SNPs in DDAH1 and 2 were determined. Progression of DN was defined as a transition from any given stage to a more advanced stage of albuminuria. Competing risk analysis was applied. Results: Plasma levels of ADMA and SDMA significantly correlated with GFR. No significant genotype-phenotype relationship was ascertained for ADMA and DDAH variants, but SNP rs805304 exhibited marginally significant association with DN. ADMA, SDMA and L-arginine/ADMA ratio standardised to GFR were identified as significant predictors of DN progression but not GFR decline using multivariate competing risk analysis. Conclusions: In our study we confirmed potentially significant role of ADMA and SDMA for the assessment of risk of DN progression in European diabetic population.

The Measurement of Asymmetric Dimethylarginine in Human Plasma by High Performance Liquid Chromatography

Objective: We aimed to establish a high performance liquid chromatography (HPLC) method to measure plasma ADMA levels easily, sensitively and reliably. Methods: We used fluorescence detection, 50 mM sodium acetate buffer/ methanol/ Tetrahydrofuran as a mobile phase (A, 82:17:1; B, 22:77:1, % v, respectively), gradient method, 338 and 425 nm excitation and emission wavelengths, respectively. Samples were derivatizated with o-Phthaldialdehyde. Results: The recovery was found as 96 to 98,3 %. Intra-assay and inter-assay coefficients of variation (CV) were 2.3% and 2.7%, respectively. Conclusion: These findings suggest that our method is suitable for routine determination of ADMA with more reliable.

The impact of pioglitazone on ADMA and oxidative stress markers in patients with type 2 diabetes

AimsTo determine whether pioglitazone 30mg daily reduces levels of ADMA in adult patients with diabetes, and whether there is improvement in markers of oxidative stress. MethodsProspective randomized cross-over placebo-controlled study of 36 adults age 40–75 years with type 2 diabetes recruited from a single academic health center. Intervention was for 12 weeks, followed by a 4-week wash-out period, followed by a second 12-week cross-over treatment period. The main outcome was comparison of the change in ADMA levels in the two treatment periods. Secondary outcomes included change in NOx and F2-isoprostanes. ResultsThirty-six patients were enrolled in the study, 31 completed the protocol; the study enrollment met the sample size required to detect a change of 18% in levels. There were no differences in ADMA, NOx and F2-isoprostanes levels in the two treatment periods. Non-study medication changes or changes in dose were infrequent, and a statin was added during the study period in only one patient. ConclusionsDespite previous animal data that showed an effect of pioglitazone on ADMA, the current study in human patients did not demonstrate any differences in ADMA, NOx, or F2-isoprostane levels. The results do not favor that pioglitazone has a significant impact on ADMA levels in human patients with diabetes.

Association of DDAH2 gene polymorphism with cardiovascular disease in Egyptian patients

1992). Elevated levels ofADMA capable of inhibiting endothelial nitric oxide syn-thase (eNOS) have been found in several disorders includ-ing coronary artery disease (CAD) (Boger 2004). Nowa-days, ADMA is regarded as a novel cardiovascular riskfactor and is degraded mainly by an intracellular enzymetermed dimethylarginine dimethylaminohydrolase (DDAH),after uptake from the circulation. DDAH degrades ADMA tocitrulline and dimethylamine (Dayoub

2225 CARDIOVASCULAR RISK IS INCREASED IN PATIENTS WITH CALCIUM OXALATE UROLITHIASIS AND CORRELATED WITH URINARY OXALATE EXCRETION

You have accessJournal of UrologyStone Disease: Evaluation & Medical Management1 Apr 20112225 CARDIOVASCULAR RISK IS INCREASED IN PATIENTS WITH CALCIUM OXALATE UROLITHIASIS AND CORRELATED WITH URINARY OXALATE EXCRETION Hasan Aydin, Faruk Yencilek, Ismet Bilger Erihan, Binnur Okan, and Kemal Sarica Hasan AydinHasan Aydin Istanbul, Turkey More articles by this author , Faruk YencilekFaruk Yencilek Istanbul, Turkey More articles by this author , Ismet Bilger ErihanIsmet Bilger Erihan Istanbul, Turkey More articles by this author , Binnur OkanBinnur Okan Istanbul, Turkey More articles by this author , and Kemal SaricaKemal Sarica Istanbul, Turkey More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.2466AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES There is a strong correlation between the development of urolithiasis and metabolic syndrome(MS) that is characterized with an increase in cardiovascular disease risk. Endothelial dysfunction (ED) is a well-known indicator of cardiovascular risk. Increase in systemic ADMA levels- an indicator of ED was reported in urolithiasis in our previous animal study. The aim of this study was to assess the cardiovascular risk in patients with urolithiasis. METHODS One hundred patients with calcium oxalate urolithiasis and 100 healthy age-matched subjects as a control group were included into this study. Framingham risk score was used for the assessment of 10-year cardiovascular risk and SCORE risk scale for 10-year fatal cardiovascular risk assessment. Oxalate, calcium, citrate, uric acid and creatinine in 24-hour urine samples were used as stone development risk factors. RESULTS Mean Framingham risk score was 10,26±9,05 (14,55±9,30 in men and 6,32±8,7 in women). It was 4,39±5,11 in healthy controls (p<0,0001). The odds-ratio for the development of cardiovascular disease was 5,18 (95% CI, 2,57–10,31) and 10 year fatal cardiovascular risk was 1,52±2,75 in patients with urolithiasis. Framingham risk score was found to be correlated with urinary oxalate excretion (p=0,002, r=0,373). Urinary oxalate excretion was also correlated with systolic blood pressure (p=0,0001, r=0,444), total cholesterol (p=0,01, r=0,293) and fasting blood glucose (p=0,007, r=0,456). CONCLUSIONS This is the first study pointing out an increased cardivascular risk in patients with calcium oxalate urolithiasis in correlation with urinary stone risk factors. Further large population-based prospective studies are needed for the confirmation. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e893 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Hasan Aydin Istanbul, Turkey More articles by this author Faruk Yencilek Istanbul, Turkey More articles by this author Ismet Bilger Erihan Istanbul, Turkey More articles by this author Binnur Okan Istanbul, Turkey More articles by this author Kemal Sarica Istanbul, Turkey More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Relationship of Asymmetric Dimethylarginine With Penile Doppler Ultrasound Parameters in Men with Vasculogenic Erectile Dysfunction

BackgroundAsymmetric dimethylarginine (ADMA), a selective endogenous nitric oxide synthase inhibitor, is elevated in many conditions associated with erectile dysfunction (ED), such as hypertension, diabetes, hyperlipidemia, and renal failure; it is also increased in men with coronary artery disease and ED. The dynamic penile colour Doppler ultrasound is considered the gold standard for the evaluation of penile vascular damage. ObjectiveWe investigated whether the extent of ultrasonographically documented penile vascular disease is associated with higher ADMA levels. Design, setting, and participantsOne hundred four consecutive ED patients (mean age: 56±9 yr) without manifest cardiovascular/atherosclerotic disease and 31 subjects with normal erectile function matched for age and traditional risk factors were studied. MeasurementsWe evaluated penile dynamic colour Doppler parameters of arterial insufficiency (peak systolic velocity) and veno-occlusive dysfunction (end diastolic velocity) and measured systemic inflammatory markers/mediators. Results and limitationsCompared to men without ED, ED patients had significantly higher ADMA levels (p<0.001). ADMA was significantly increased in patients with severe arterial insufficiency (PSV<25cm/s) compared to subjects with borderline insufficiency and men with normal penile arterial function (p<0.001, by analysis of variance). Multivariable analysis adjusting for age, mean pressure, other risk factors, high-sensitivity C-reactive protein, testosterone, and treatment showed independent inverse association between ADMA level and peak systolic velocity (p<0.01). The combination of higher ADMA level with arterial insufficiency showed greater impact on 10-yr risk of a cardiovascular event compared to either parameter alone. ConclusionsADMA level is independently associated with ultrasonographically documented poor penile arterial inflow. This finding underlines the important role of ADMA as a marker of penile arterial damage and implies a contribution of this compound to the pathophysiology of generalised vascular disease associated with ED.

Association Between Asymmetric Dimethylarginine and the Severity of Coronary Artery Disease in Patients with Chronic Kidney Disease

maTERial and mETHOdS: Eighty-eight (88) consecutive patients with decreased renal function (glomerular filtration rate (GFR) between 90 and 30 ml/min), undergoing cardiac catheterization for proven or clinically suspected coronary artery disease were enrolled at the study. Serum levels of creatinine, ADMA, nitric oxide (NO), calcium, phosphate, total cholesterol, HDL and LDL fractions, triglycerides were determined using measurement techniques. The Gensini scoring system was used for the detection of the severity of coronary atherosclerosis.

Protective effect of HDL on endothelial NO production: the role of DDAH/ADMA pathway

Accumulating studies have demonstrated that the dimethylarginine dimethylaminohydrolase/asymmetric dimethylarginine (DDAH/ADMA) system is a novel pathway for modulating nitric oxide (NO) production. The aim of this study was to investigate whether the protective effect of high density lipoprotein (HDL) on endothelial NO production was related to its effect on DDAH/ADMA pathway. Human umbilical vein endothelial cells (HUVECs) were prior exposed to HDL (10, 50, or 100 μg/ml) for 1 h, and then incubated with oxidized low density lipoprotein (ox-LDL) (100 μg/ml) for 24 h. The cultured medium was collected for measuring the concentration of NO and ADMA. The cells were collected for measuring the mRNA and protein expression of DDAH-II as well as DDAH activity. HUVECs treated with ox-LDL (100 μg/ml) for 24 h significantly decreased the concentration of NO, the mRNA and protein expression of DDAH-II as well as DDAH activity and increased the level of ADMA. Pretreatment with HDL (10, 50, or 100 μg/ml) could counteract these changes induced by ox-LDL (100 μg/ml). HDL significantly increased the attenuated endothelial cell NO production induced by ox-LDL, which was attributed to its effect on DDAH/ADMA pathway.

Determination of asymmetric dimethyl arginine in human serum by liquid chromatography-tandem mass spectrometry: clinical application in hypertensive subjects

Asymmetric dimethylarginine (ADMA), an endogenous competitive inhibitor of nitric oxide synthase plays an important role in endothelial dysfunction processes. Recent studies have linked high ADMA levels with several pathological conditions. The interest as a marker of endothelial dysfunction has increased in the last few years. In this paper, a method for serum ADMA quantification by liquid chromatography tandem mass spectrometry has been described. To test the utility in a pathological condition ADMA levels in hypertensive subjects have been measured. HPLC separation was performed by hydrophilic interaction chromatography using acetonitrile/water containing 0.1% formic acid and 20 mmol/L ammonium formate. Selected reaction monitoring was performed following the transitions m/z 203.1→46.4 for ADMA and 210.1→46.3 for the internal standard [2H7]ADMA. The method was linear up to 10 μmol/L, limit of detection and limit of quantification were 0.005 μmol/L and 0.01 μmol/L, respectively. Recovery was higher than 96%. Intra- and inter-assay imprecision were lower than 6%. The accuracy, expressed as bias %, was <2.5. ADMA in "healthy" subjects ranged from 0.343 to 0.608 μmol/L and resulted significantly lower than that measured in hypertensive subjects (p<0.001). The method developed is selective and sensitive, thus suitable not only for research purposes, but also for routinely work.

Peripheral Vascular Dysfunction in Chronic Kidney Disease

There is an increased prevalence of cardiovascular disease- (CVD-) related mortality in patients with chronic kidney disease (CKD). Endothelial dysfunction is a primary event in the development of atherosclerosis and hypertension and likely contributes to the elevated cardiovascular risk in CKD. Endothelial dysfunction has been shown to occur in the peripheral vasculature of patients with both severe and moderate CKD. Mechanisms include oxidative stress, L-arginine deficiency, and elevated plasma levels of ADMA. Interventions designed to restore vascular function in patients with CKD have shown mixed results. Evidence from cell culture studies suggest that the accumulation of uremic toxins inhibits L-arginine transport and reduces nitric oxide production. The results of these studies suggest that endothelial dysfunction may become less reversible with advancing kidney disease. The purpose of this paper is to present the current literature pertaining to potential mechanisms of peripheral vascular dysfunction in chronic kidney disease and to identify possible targets for treatment.

Asymmetric dimethylarginine in ELBW newborns exposed to chorioamnionitis

We measured circulating ADMA concentrations in a group of very premature newborns at birth and during the first week of life. ADMA levels resulted significantly higher in infants born to mothers with histologic chorioamnionitis than in infants delivered for other maternal or fetal indications, both at birth and through the first week of life. We speculate that ADMA might be involved in the complex biological events associated with fetal exposure to chorioamnionitis.

Relationship between L-arginine/asymmetric dimethylarginine, homocysteine, folic acid, vitamin B levels, and coronary artery ectasia

Coronary artery ectasia (CAE) is characterized by an abnormal dilatation of the coronary arteries. The ratio of L-arginine/asymmetric dimethylarginine (ADMA) and homocysteine are important factors for endothelial function. In this study, we investigate the ratio of L-arginine/ADMA, homocysteine, and folic acid/vitamin B levels in patients with CAE. Forty patients diagnosed with CAE using coronary angiography were included in the study (24 male; mean age, 56 ± 11 years). The control group consisted of 30 patients who had normal coronary arteries as determined by coronary angiography (11 male; mean age, 54 ± 8 years). The ratio of L-arginine/ADMA and plasma homocysteine was measured using high-performance liquid chromatography. The L-arginine/ADMA ratio and L-arginine levels were significantly lower in the CAE group compared with the control group (110 ± 27 vs. 149 ± 77, P=0.02 and 157 ± 32 μmol/l vs. 187 ± 59 μmol/l, P=0.02, respectively). Plasma ADMA levels were similar in the two groups. Patients with CAE had higher plasma homocysteine levels (P=0.01). Plasma folic acid, vitamin B6, and vitamin B12 levels were similar between the two groups. This study shows that patients with CAE have a lower L-arginine/ADMA ratio and higher plasma homocysteine levels. These results show a potential relationship between endothelial dysfunction and CAE.

Inflammatory-metabolic parameters in obese and nonobese normoandrogenemic polycystic ovary syndrome during metformin and oral contraceptive treatment

Our aim was to evaluate the optimal treatment strategy addressing cardiovascular risk in obese and nonobese patients with polycystic ovary syndrome (PCOS). We planned a prospectıve randomized clinical study. Normoandrogenemic and oligoamenorrheic women with PCOS and impaired glucose tolerance (n = 96) were enrolled in the study. Six months of treatment with metformin HCL or oral contraceptive pills (OCPs) were given to the patients. Group 1 were obese and receiving metformin. Group 2 were obese and receiving OCPs. Group 3 were nonobese and receiving metformin, and Group 4 were nonobese receiving OCPs. ADMA, homocysteine, high sensitive C-reactive protein (hs-CRP) and homeostasis model assessment estimate of insulin resistance (HOMA-IR) were investigated. ADMA, homocysteine, hs-CRP and HOMA-IR were similar in obese and nonobese groups before the treatment. After 6 months of treatment, a significant decrease was observed in ADMA, homocysteine and HOMA-IR levels in Groups 1 and 3. An increase in ADMA and hs-CRP levels was observed in Groups 2 and 4. In this study, metformin treatment leads to improvement in hormonal and metabolic parameters and decreases ADMA and homocysteine levels possibly independent of BMI. However, the use of oral contraceptives in obese and nonobese patients with PCOS with impaired glucose tolerance increases ADMA and hs-CRP levels and creates an increase in the metabolic risk.

E0305 The effect of profilin-1 on vascular injury caused by advanced glycation end products

ObjectiveThe aims of this study were to explore the effect of Profilin-1 on vascular injury caused by advanced glycation end products, So as to provide a new therapeutic approach with...

P33 Inter-ethnic difference of ADMA levels in healthy pregnancy and preeclampsia

P33 Inter-ethnic difference of ADMA levels in healthy pregnancy and preeclampsia

Plasma levels of asymmetric dimethylarginine in patients with biopsy-proven nonalcoholic fatty liver disease

Asymmetric (ADMA) and symmetric dimethylarginine (SDMA) are produced by breakdown of proteins that have been methylated posttranslationally at an arginine residue. Plasma levels of ADMA are elevated in insulin resistance states. Nonalcoholic fatty liver disease (NAFLD) is associated with insulin resistance and varying degrees of hepatic dysfunction. Because ADMA is metabolized in the liver, we hypothesized that ADMA levels will be high in patients with NAFLD as a consequence of hepatic dysfunction and insulin resistance. Plasma levels of ADMA, SDMA, total homocysteine, glucose, and insulin were measured in nondiabetic patients with biopsy-proven NAFLD (11 steatosis and 24 nonalcoholic steatohepatitis) and 25 healthy subjects. Plasma ADMA levels were significantly higher ( P = .029 ) in patients with biopsy-proven NAFLD (0.43 ± 0.21 μmol/L) compared with controls (0.34 ± 0.10 μmol/L). However, when adjusted for insulin resistance (homeostasis model assessment), the difference between 2 groups was not evident. Plasma SDMA levels were similar in all 3 groups. Plasma levels of ADMA were positively correlated with plasma total homocysteine levels ( P = .003). Plasma levels of SDMA were negatively correlated with estimated glomerular filtration rate ( P = .016) and positively correlated with plasma total homocysteine levels ( P = .003). The ratio of ADMA/SDMA was positively correlated with body mass index ( P = .027). Elevated plasma concentrations of ADMA in biopsy-proven NAFLD were primarily related to insulin resistance. Hepatic dysfunction in NAFLD does not appear to make significant contribution to changes in plasma methylarginine levels.