Asymmetric Dimethylarginine Levels Research Articles

Pan-methylarginine antibody generation using PEG linked GAR motifs as antigens.

Arginine methylation is a prevalent posttranslational modification which is deposited by a family of protein arginine methyltransferases (PRMTs), and is found in three different forms in mammalian cells: monomethylarginine (MMA), asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA). Pan-methylarginine antibodies are critical for identifying proteins that are methylated on arginine residues, and are also used for evaluating signaling pathways that modulate this methyltransferase activity. Although good pan-MMA, -ADMA and -SDMA antibodies have been developed over the years, there is still room for improvement. Here we use a novel antigen approach, which involves the separation of short methylated motifs with inert polyethylene glycol (PEG) linkers, to generate a set of pan antibodies to the full range of methylarginine marks. Using these antibodies, we observed substrate scavenging by PRMT1, when PRMT5 activity is blocked. Specifically, we find that the splicing factor SmD1 displays increased ADMA levels upon PRMT5 inhibitor treatment. Furthermore, when the catalysis of both SDMA and ADMA is blocked with small molecule inhibitors, we demonstrate that SmD1 and SMN no longer interact. This could partially explain the synergistic effect of PRMT5 and type I PRMT inhibition on RNA splicing and cancer cell growth.

Combination of Electrochemistry and Mass Spectrometry to Study Nitric Oxide Metabolism and Its Modulation by Compound K in Breast Cancer Cells.

The levels of l-arginine and asymmetric dimethylarginine (ADMA) and the amount of the nitric oxide (NO) production have recently been linked to breast cancer and pharmaceutical effect evaluation. Herein, a method combining electrochemistry and high-resolution mass spectrometry (HRMS) was established and used to study NO metabolism and its modulation by ginsenoside compound K (CK) in breast cancer cells. Platinum nanoparticles-decorated fluorine tin oxide was employed as an electrochemical sensor for in situ detection of NO release, while HRMS was used for the analysis of the NO-related metabolites. Through the combination of the electrochemical and HRMS results, decreases in arginine and NO and increases in ADMA and ornithine were observed after modulation by CK, and two highly correlated metabolic pathways including arginine and proline metabolism and vascular smooth muscle contraction were found. This method offers a new strategy for fast evaluation of pharmaceutical efficacy based on NO metabolism.

Serum asymmetric dimethylarginine (ADMA) level and cognitive dysfunction in diabetic patients

Serum asymmetric dimethylarginine (ADMA) level and cognitive dysfunction in diabetic patients

Effects of Physical Prehabilitation on the Dynamics of the Markers of Endothelial Function in Patients Undergoing Elective Coronary Bypass Surgery.

Our aim in this study was to evaluate the effect of physical training performed before CABG on the perioperative dynamics of the serum levels of asymmetric dimethylarginine (ADMA) and endothelin-1 (ET-1) of patients with stable coronary heart disease (CHD). Patients in the preoperative period were randomized into two groups: the training group (n = 43) underwent high-intensity treadmill training; the patients in the control group (n = 35) received no training before the procedure. The serum concentrations of ADMA and ET-1 were determined in the perioperative period, and the course of the early postoperative period was analyzed. In the training group, we found a significantly lower incidence of postoperative complications during hospital stays (p = 0.013). At the end of the training program, the ADMA levels were 1.8 times higher in the controls than in the training group (p = 0.001). We found that type 2 diabetes increased the probability of complications by 12 times (OR: 12.3; 95% CI: 1.24–121.5; p = 0.03), as well as elevating the concentration of ET-1 on the eve of surgery (OR: 10.7; 95% CI: 1.4–81.3; p = 0.02). Physical prehabilitation reduced the likelihood of complications nine times (OR: 0.11; 95% CI: 0.02–0.83; p = 0.03). The AUC was 0.851 ± 0.07 (95% CI: 0.71–0.98). The obtained results indicate the benefit of physical training during the prehabilitation stage since it can help to preserve endothelial function.

Diabetes acts on mortality in hemodialysis patients predicted by asymmetric dimethylarginine and inflammation

BackgroundThe mortality rate of diabetic patients on dialysis is higher than that of non-diabetic patients. Asymmetric dimethylarginine and inflammation are strong predictors of death in hemodialysis. This study aimed to evaluate asymmetric dimethylarginine and C-reactive protein interaction in predicting mortality in hemodialysis according to the presence or absence of diabetes. MethodsAsymmetric dimethylarginine and C-reactive protein were measured in 202 patients in maintenance hemodialysis assembled from 2011 to 2012 and followed for four years. Effect modification of C-reactive protein on the relationship between asymmetric dimethylarginine and all-cause mortality was investigated dividing the population into four categories according to the median of asymmetric dimethylarginine and C-reactive protein. ResultsAsymmetric dimethylarginine and C-reactive protein levels were similar between diabetics and non-diabetics. Asymmetric dimethylarginine – median IQR μM – (1.95 1.75–2.54 versus 1.03 0.81–1.55 P=0.000) differed in non-diabetics with or without evolution to death (HR 2379 CI 1.36–3.68 P=0.000) and was similar in diabetics without or with evolution to death. Among non-diabetics, the category with higher asymmetric dimethylarginine and C-reactive protein levels exhibited the highest mortality (69.0% P=0.000). No differences in mortality were seen in diabetics. A joint effect was found between asymmetric dimethylarginine and C-reactive protein, explaining all-cause mortality (HR 15.21 CI 3.50–66.12 P=0.000). ConclusionsAsymmetric dimethylarginine is an independent predictor of all-cause mortality in non-diabetic patients in hemodialysis. Other risk factors may overlap asymmetric dimethylarginine in people with diabetes. Inflammation dramatically increases the risk of death associated with high plasma asymmetric dimethylarginine in hemodialysis.

Correlation of Asymmetric Dimethyl Arginine Level to Sickle Retinopathy in Children With Sickle Cell Disease.

Asymmetric dimethyl arginine (ADMA) is a competitive inhibitor of nitric oxide synthetase especially in L-arginine deficiency, which is the case in sickle cell disease (SCD). we aimed to assess the level of ADMA in children with sickle retinopathy and to correlate it to the degree of retinopathy. In this cross-sectional study 40 children with SCD were included, 20 of them with sickle cell retinopathy (SCR) (group I), 20 with normal fundus examination (group II), and another 20 healthy children served as controls (group III). We measured ADMA level by ELISA and performed fundus examination. Seventeen of the 20 children included in group I had Grade I retinopathy (85%), 2 children had Grade II retinopathy (10%), and 1 child had Grade III retinopathy (5%). ADMA was significantly higher in SCD than controls ( P -value <0.001), and it was even higher in patients with SCR compared those without retinopathy ( P -value <0.002), and there was positive linear correlation between ADMA and the grade of retinopathy. The type of retinopathy detect in the studied patients was the nonproliferative type. In conclusion, ADMA is elevated in children with SCD, and its level is even higher in those who develop SCR.

Effects of green cardamom supplementation on serum levels of Hs-CRP, dimethylarginine, nitric oxide and blood pressure in patients with type 2 diabetes: A randomized, double-blind, placebo controlled, clinical trial

PurposeCardamom contains phytochemicals with a potential role in lowering blood pressure (BP) and improving the inflammatory status in type 2 diabetes mellitus (T2DM). However, only a few studies have been carried out to evaluate the effect of cardamom in these patients. Therefore, the aim of this study was to assess the effects of green cardamom supplementation on serum high-sensitivity C–reactive protein (hs-CRP), asymmetric dimethylarginine (ADMA), nitric oxide (NO), systolic blood pressure (SBP) and diastolic blood pressure (DBP) in patients with T2DM. Materials and MethodsIn this double blind, randomized, controlled clinical trial, 83 patients with T2DM were divided randomly into two groups, including the green cardamom group (3 g/d, n = 41) and placebo group (3 g/d, n = 42). All patients received the supplements for 10 weeks. Serum levels of hs-CRP, ADMA, NO, SBP and DBP were measured at baseline and week 10. ResultsThe intention-to-treat (ITT) analysis showed a decrease in mean serum hs-CRP levels [from 5.22 (3.56) to 4.81 ng/ml (3.72); p < 0.05] along with a significant increase in mean serum NO levels [from 65.6 (22.6) to 84 Mµ (26.3)], (p < 0.001). There was a significant decrease in mean SBP in the cardamom group [from 125.2 (12.4) to 119.4 mm/hg (11.8)] compared to the placebo group [128.1 (15.6) to 126.7 mmHg (13.5)] (p < 0.001). Furthermore, ITT analysis showed a decrease in mean SBP [from 125.6 (12.2) to 120 mmHg (11.59)] (p < 0.001). Changes in serum ADMA and DBP levels were not statistically significant between the two groups. In addition, in Per-Protocol (PP) analysis, a significant decrease was found in mean serum hs-CRP levels in the cardamom group [from 5.25 (3.66) to 4.87 ng/ml (3.8)] compared to the placebo group [4.4 (3) to 5.7 ng/ml (4.2)]; (p < 0.05), along with a significant increase in mean serum NO levels in the cardamom group [from 62.9 (18) to 82.5 Mµ (24.6)] compared to the placebo group [70.7 (28) to 72.1 Mµ (25.8)]; (p < 0.001). ConclusionGreen cardamom may have beneficial effects on SBP, NO and hs-CRP levels in patients with T2DM. Improvement in BP and inflammatory markers can help prevent the complications from T2DM including cardiovascular risk in these patients.

Opuntia ficus-indica Alleviates Particulate Matter 10 Plus Diesel Exhaust Particles (PM10D)—Induced Airway Inflammation by Suppressing the Expression of Inflammatory Cytokines and Chemokines

Particulate matter (PM) exposure may cause adverse health effects such as respiratory disorders. We evaluated the protective effects of various Opuntia ficus-indica (OFI) extracts on airway inflammation associated with exposure to PM10D with an aerodynamic diameter <10 μm (PM10) and diesel exhaust particles (DEP). BALB/c mice were exposed to PM10D via intranasal tracheal injection three times over a period of 12 days and various OFI extracts (water, 30% ethanolic, or 50% ethanolic extracts) were administered orally for 12 days. All OFI extracts suppressed neutrophil infiltration and the number of immune cells (CD3+/CD4+, CD3+/CD8+, and Gr-1+/CD11b) in bronchoalveolar lavage fluid (BALF) and lungs. OFI extracts decreased the expression of cytokines and chemokines, including chemokine (C-X-C motif) ligand (CXCL)-1, interleukin (IL)-17, macrophage inflammatory protein-2, tumor necrosis factor (TNF)-α, cyclooxygenase-2, IL-1α, IL-1β, IL-5, IL-6, transient receptor potential cation channel subfamily V member 1, and mucin 5AC, and inhibited IRAK-1, TNF-α, and CXCL-1 localization in BALF and lungs of mice with PM10D-induced airway inflammation. Serum asymmetric and symmetric dimethyl arginine levels were also decreased by OFI extracts treatment. Moreover, all OFI extracts restored histopathological damage in the trachea and lungs of mice with PM10D-induced airway inflammation. These results indicate that OFI extracts may be used to prevent and treat airway inflammation and respiratory diseases.

Metabolomic signatures for the longitudinal reduction of muscle strength over 10 years

BackgroundSkeletal muscles are essential components of the neuromuscular skeletal system that have an integral role in the structure and function of the synovial joints which are often affected by osteoarthritis (OA). The aim of this study was to identify the baseline metabolomic signatures for the longitudinal reduction of muscle strength over 10 years in the well-established community-based Tasmanian Older Adult Cohort (TASOAC).MethodsStudy participants were 50–79 year old individuals from the TASOAC. Hand grip, knee extension, and leg strength were measured at baseline, 2.6-, 5-, and 10-year follow-up points. Fasting serum samples were collected at 2.6-year follow-up point, and metabolomic profiling was performed using the TMIC Prime Metabolomics Profiling Assay. Generalized linear mixed effects model was used to identify metabolites that were associated with the reduction in muscle strength over 10 years after controlling for age, sex, and BMI. Significance level was defined at α=0.0004 after correction of multiple testing of 129 metabolites with Bonferroni method. Further, a genome-wide association study (GWAS) analysis was performed to explore if genetic factors account for the association between the identified metabolomic markers and the longitudinal reduction of muscle strength over 10 years.ResultsA total of 409 older adults (50% of them females) were included. The mean age was 60.93±6.50 years, and mean BMI was 27.12±4.18 kg/m2 at baseline. Muscle strength declined by 0.09 psi, 0.02 kg, and 2.57 kg per year for hand grip, knee extension, and leg strength, respectively. Among the 143 metabolites measured, 129 passed the quality checks and were included in the analysis. We found that the elevated blood level of asymmetric dimethylarginine (ADMA) was associated with the reduction in hand grip (p=0.0003) and knee extension strength (p=0.008) over 10 years. GWAS analysis found that a SNP rs1125718 adjacent to WISP1gene was associated with ADMA levels (p=4.39*10-8). Further, we found that the increased serum concentration of uric acid was significantly associated with the decline in leg strength over 10 years (p=0.0001).ConclusionOur results demonstrated that elevated serum ADMA and uric acid at baseline were associated with age-dependent muscle strength reduction. They might be novel targets to prevent muscle strength loss over time.

Serum asymmetric dimethylarginine level correlates with the progression and prognosis of amyotrophic lateral sclerosis.

Background and purpose:The aim was to investigate the association between serum asymmetric dimethylarginine (ADMA) levels and the progression and prognosis of amyotrophic lateral sclerosis (ALS), and to compare cerebrospinal fluid (CSF) and serum ADMA levels with other biomarkers of ALS.MethodsSerum ADMA levels of sporadic ALS patients (n = 68), disease control patients (n = 54) and healthy controls (n = 20) were measured using liquid chromatography tandem mass spectrometry. Correlations of the ADMA level and other markers (nitric oxide and neurofilament light chain levels) were analyzed. Changes in the ALS Functional Rating Scale Revised (ALSFRS‐R) score from the onset of disease (ALSFRS‐R pre‐slope) was used to assess disease progression. Survival was evaluated using the Cox proportional hazards model and Kaplan–Meier analysis.ResultsThe serum ADMA level was substantially higher in patients with ALS than in healthy controls and disease controls. Serum ADMA level correlated with CSF ADMA level (r = 0.591, p < 0.0001) and was independently associated with the ALSFRS‐R pre‐slope (r = 0.505, p < 0.0001). Patients with higher serum ADMA levels had less favorable prognoses. CSF ADMA level significantly correlated with CSF neurofilament light chain level (r = 0.456, p = 0.0002) but not with nitric oxide level (r = 0.194, p = 0.219).ConclusionSerum ADMA level is an independent biomarker of ALS disease progression and prognosis and reflects the degree of motor neuron degeneration.

Effect of profilin-1 on the asymmetric dimethylarginine-induced vascular lesion associated hypertension

Abstract Funding Acknowledgements Type of funding sources: None. OnBehalf Guohua Ni Objective Previous studies have demonstrated that the levels of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide (NO) synthesis, are strongly associated with hypertension, diabetes, and cardiovascular diseases. Profilin-1, an actin-binding protein, has been documented to be involved in endothelial injury and in the proliferation of vascular smooth muscle cells (VSMCs) resulting from hypertension. However, the role of profilin-1 in ADMA-induced vascular injury in hypertension remains largely unknown. Methods Forty healthy subjects and forty-two matched patients with essential hypertension were enrolled, and the related indexes of vascular injury in plasma were detected. Rat aortic smooth muscle cells (RASMCs) were treated with different concentrations of ADMA for different periods of time and transfected with profilin-1 shRNA to interrupt the expression of profilin-1. To determine the role of the Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) pathway, RASMCs were pretreated with AG490 or rapamycin. The expression of profilin-1 was tested using real-time PCR and western blot analysis. Cell proliferation was measured by flow cytometry and MTT assays. Results Compared with healthy subjects, the levels of ADMA and profilin-1 were markedly elevated in hypertensive individuals, while the levels of NO were significantly decreased(P &amp;lt; 0.05). In vitro, studies showed ADMA induced profilin-1 expression in a concentration- and time-dependent manner in RASMCs (P &amp;lt; 0.05), concomitantly with promoting the proliferation of RASMCs. Furthermore, ADMA-mediated proliferation of RASMCs and up-regulation expression of profilin-1 were inhibited by blockade of the JAK2/STAT3 pathway or knockdown of profilin-1. Conclusions Profilin-1 implicated in the ADMA-mediated vascular lesions in hypertension. Abstract Figure 12 Abstract Figure 3

The role of oxidative stress markers in Indonesian chronic kidney disease patients: a cross sectional study

Background: Several aspects of chronic kidney disease (CKD) such as the incidence rate and mortality rate are concerning. Oxidative stress contributes to progression and mortality in patients with CKD; however, a specific correlation between several markers of oxidative stress and the estimated glomerular filtration rate (eGFR) and albumin-creatinine ratio (ACR) in the Indonesian population has not been sufficiently described yet. Methods: This study was an analytic observational study with a sample of 56 patients with CKD in Universitas Airlangga Hospital, Surabaya, Indonesia, from December 2019 – March 2020. The markers for oxidative stress investigated were urinary 8-hydroxy-2 deoxyguanosine (8-OHdG), serum symmetric dimethylarginine (SDMA) and asymmetric dimethylarginine (ADMA). The correlations between each variable of oxidative stress and CKD were analyzed using Pearson analysis. Results: There was a positive correlation between 8-OHdG and eGFR (p=0.00, r=0.51); however, there was a negative correlation between 8-OHdG and ACR (p=0.025, r=-0.30). SDMA and eGFR showed a negative correlation (p=0.00, r=-0.648), while SDMA and ACR showed a positive correlation (p=0.03, r=0.349). ADMA showed a negative correlation with eGFR (p=0.00, r=-0.476). There were significantly decreased 8-OHdG but increased ADMA and SDMA as the CKD stage progressed (p=0.001, p=0.00, and p = 0.00, respectively). Higher urine 8-OHdG was detected in patients without history of hemodialysis, whereas ADMA and SDMA showed higher value in patients with hemodialysis (p=0.00, p=0.00, and p=0.004, respectively), patients with history of diabetes mellitus (DM) had higher mean 8-OHdG (p 0.000) yet lower serum ADMA and SDMA (p=0.004 and p=0.003, respectively). Conclusions: In patients with CKD in Indonesia, the markers for oxidative stress 8-OHdG, SDMA, and ADMA are correlated with eGFR and ACR levels. There were also significant difference in 8-OHdG, SDMA, and ADMA levels among CKD stages, between dialysis vs non dialysis, and DM vs non DM patients.

Association of Endothelin-I and A symmetric Dimethylarginine Levels with Insulin Resistance in Type-2 Diabetes Mellitus Patients

Endothelin-I (ET-I) is one of the potent vasoconstrictors secreted from endothelial cells when needed. Many studies revealed the elevation of serum ET-I with human diabetes and microangiopathies. Since insulin resistance is a case of mixed diabetic and pre-diabetic cases, many risk factors beyond obesity and inflammation are proposed. The current study aims to demonstrate the association between serum ET-I and asymmetric dimethylarginine (ADMA) and insulin resistance in type 2 diabetes mellitus (T2DM). Sera of 73 subjects were enrolled currently (control= 35 subjects, and 38 with T2DM for more than 7 years), aged (40-60) years old, with distinct body mass index (BMI) ≤ 25 for control volunteers and (BMI) ≥ 25 for obesity and diabetes patients. Peripheral serum ET-I and ADMA levels were significantly (P≤ 0.0001) higher in T2DM than the control subjects. Receiver operating characteristic curve analysis regarded ET-I and ADMA as good markers for T2DM disease and insulin resistance, correlations between ET-I and anthropometrics revealed a strong increase of urotensin-II (UII), ADMA, homeostatic model assessment for insulin resistance (HOMA-IR) and hemoglobin A1C (HbA1C) with an increase of ET-I. These results are supported by the data of multiple regression analysis, showing that HOMA-IR, HbA1C, UII, BMI, and mean arterial pressure (MAP) are related to ET-I independently. The endothelin-I and ADMA had a positive relationship with increase insulin resistance and may serve as prognostic and diagnostic clinical biomarkers of insulin resistance. Collectively, Therefore, these measurements could evaluate the incidence of DM, and help to better rise up the knowledge about the progression of DM complications.

Curcumin improves cardiac fibrosis by inhibiting endothelial-mesenchymal transition through NRF2-DDAH-ADMA-NO pathway

The present study analyzed the correlations between curcumin(Cur), nuclear factor E2 related factor 2(NRF2)-dimethylarginine dimethylaminohydrolase(DDAH)-asymmetric dimethylarginine(ADMA)-nitric oxide(NO) pathway, and endothelial-mesenchymal transition(EndMT) based on SD rats with cardiac fibrosis, and explored the effect and mechanism of Cur in resisting cardiac fibrosis to provide an in-depth theoretical basis for its clinical application in the treatment of heart failure. The cardiac fibrosis model was induced by subcutaneous injection of isoprenaline(Iso) in rats. Thirty-two rats were randomly divided into a control group, a model group, a low-dose Cur group(100 mg·kg~(-1)·d~(-1)), and a high-dose Cur group(200 mg·kg~(-1)·d~(-1)), with eight in each group. After 21 days of treatment, cardiac function was detected by echocardiography, degree of cardiac fibrosis by Masson staining, expression of CD31 and α-SMA by pathological staining, expression of VE-cadherin, vimentin, NRF2, and DDAH by Western blot, and ADMA level by HPLC. Compared with the model group, the Cur groups showed alleviated cardiac fibrosis, accompanied by increased CD31 and VE-cadherin expression and decreased α-SMA and vimentin expression, indicating relieved EndMT. Additionally, DDAH and NRF2 levels were elevated and ADMA and NO expression declined. Cur improves cardiac fibrosis by inhibiting EndMT presumedly through the NRF2-DDAH-ADMA-NO pathway.

Effect of calcium and vitamin D supplementation on the clinical, hormonal, and metabolic profile in non-obese women with polycystic ovary syndrome

In this study, we investigated the effect of calcium and vitamin D (Ca/Vit D) supplementation on the clinical, hormonal, and metabolic profile of patients with low vitamin D levels. In addition, we investigated the effect of Ca/Vit D supplementation on asymmetric dimethylarginine (ADMA) level in patients with polycystic ovary syndrome (PCOS). In total, 75 patients aged 19-35years, with a normal body mass index and a diagnosis of PCOS and Vit D deficiency/insufficiency, were included in the study. Patients received 50,000IU of vitamin D3 once a week for 8weeks. Afterward, 2500mg calcium carbonate equivalent to 1000mg calcium ion and 9.68mg cholecalciferol equivalent to 880IU vitamin D3 were administered orally as a maintenance treatment once a day. The mean age of the patients was 21.7 ± 3.5. After Ca/Vit D supplementation, Vit D levels significantly increased compared to baseline (8.6ng/ml) levels. An increase in SHBG levels (p < 0.001), a decrease in total testosterone, FAI (p = 0.042), and ADMA levels (p < 0.001) were observed in the first and third months compared to the onset. Significant improvement compared to baseline was observed in menstrual irregularity and median mFG score. Ca/Vit D supplementation can improve PCOS symptoms such as menstrual dysfunction, hirsutism, and hyperandrogenism. It may be effective in reducing the risk of cardiovascular disease in patients with PCOS later in life by decreasing ADMA levels, which is an indicator of endothelial dysfunction.

A Recombinant Dimethylarginine Dimethylaminohydrolase-1-Based Biotherapeutics to Pharmacologically Lower Asymmetric Dimethyl Arginine, thus Improving Postischemic Cardiac Function and Cardiomyocyte Mitochondrial Activity.

High serum levels of asymmetric dimethyl arginine (ADMA) are associated with cardiovascular disease and mortality. Pharmacological agents to specifically lower ADMA and their potential impact on cardiovascular complications are not known. In this study, we aimed to investigate the effect of specific lowering of ADMA on myocardial response to ischemia-reperfusion injury (I/R) and direct effects on cardiomyocyte function. Effects of recombinant dimethylarginine dimethylaminohydrolase (rDDAH)-1 on I/R injury were determined using isolated mouse heart preparation. Respiration capacity and mitochondrial reactive oxygen species (ROS) generation were determined on mouse cardiomyocytes. Our results show that lowering ADMA by rDDAH-1 treatment resulted in improved recovery of cardiac function and reduction in myocardial infarct size in mouse heart response to I/R injury (control 22.24 ±4.60% versus rDDAH-1 15.90 ±4.23%, P < 0.01). In mouse cardiomyocytes, rDDAH-1 treatment improved ADMA-induced dysregulation of respiration capacity and decreased mitochondrial ROS. Furthermore, in human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes with impaired contractility under hypoxia and high ADMA, rDDAH-1 treatment improved recovery and beating frequency (P < 0.05). rDDAH-1 treatment selectively modified I/R-induced myocardial cytokine expression, resulting in reduction in proinflammatory cytokine IL-17A (P < 0.001) and increased expression of anti-inflammatory cytokines IL-10 and IL-13 (P < 0.01). Further in vitro studies showed that IL-17A was the predominant and common cytokine modulated by ADMA-DDAH pathway in heart, cardiomyocytes, and endothelial cells. These studies show that lowering ADMA by pharmacological treatment with rDDAH-1 reduced I/R injury, improved cardiac function, and ameliorated cardiomyocyte bioenergetics and beating activity. These effects may be attributable to ADMA lowering in cardiomyocytes and preservation of cardiomyocyte mitochondrial function. SIGNIFICANCE STATEMENT: The pathological role of asymmetric dimethyl arginine (ADMA) has been demonstrated by its association with cardiovascular disease and mortality. Currently, pharmacological drugs to specifically lower ADMA are not available. The present study provides the first evidence that lowering of ADMA by recombinant recombinant dimethylarginine dimethylaminohydrolase (rDDAH)-1 improved postischemic cardiac function and cardiomyocyte bioenergetics and beating activity. Our studies suggest that lowering of ADMA by pharmacologic treatment offers opportunity to develop new therapies for the treatment of cardiovascular and renal disease.

Association of asymmetric dimethylarginine with the pathological process of persistent pulmonary hypertension of the newborn.

To study the change in asymmetric dimethylarginine (ADMA) in the circulation system of full-term infants with persistent pulmonary hypertension of the newborn (PPHN) and its association with treatment response, as well as the possibility of ADMA as a therapeutic target and a marker for treatment response. A prospective study was performed. A total of 30 full-term neonates who were diagnosed with PPHN within 3 days after birth were enrolled as the PPHN group, and the neonates without PPHN, matched for gestational age and age, who were treated or observed in the department of neonatology were enrolled as the control group. Serum samples were collected on days 1, 7, and 14 of treatment. The high-performance liquid chromatography-tandem mass spectrometry was used to measure the serum concentrations of L-arginine, ADMA, and its isomer symmetric dimethylarginine (SDMA). For the neonates in the control group, the serum concentrations of ADMA and L-arginine continuously increased and the serum concentration of SDMA continuously decreased within the first 14 days of treatment. On days 1 and 14, there was no significant difference in the serum concentration of ADMA between the control and PPHN groups (P>0.05). On day 7, the PPHN group had a significantly higher serum concentration of ADMA than the control group (P<0.05), while there were no significant differences in serum concentrations of SDMA or L-arginine (P>0.05). Moreover, after 7 days of treatment, the PPHN neonates with a systolic pulmonary arterial pressure (sPAP) of >35 mmHg had a significantly higher serum concentration of ADMA than those with an sPAP of ≤35 mm Hg. There are continuous increases in the ADMA concentration and the ADMA/SDMA ratio in the circulation system of full-term infants within the first 2 weeks after birth, and this process is accelerated by the pathological process of PPHN, suggesting that ADMA may be involved in the pathologic process of PPHN. A high level of ADMA is associated with the resistance to PPHN treatment, suggesting that inhibition of ADMA might be a potential target of drug intervention to improve the treatment response of PPHN.

Mechanical force promotes dimethylarginine dimethylaminohydrolase 1-mediated hydrolysis of the metabolite asymmetric dimethylarginine to enhance bone formation

Mechanical force is critical for the development and remodeling of bone. Here we report that mechanical force regulates the production of the metabolite asymmetric dimethylarginine (ADMA) via regulating the hydrolytic enzyme dimethylarginine dimethylaminohydrolase 1 (Ddah1) expression in osteoblasts. The presence of -394 4 N del/ins polymorphism of Ddah1 and higher serum ADMA concentration are negatively associated with bone mineral density. Global or osteoblast-specific deletion of Ddah1 leads to increased ADMA level but reduced bone formation. Further molecular study unveils that mechanical stimulation enhances TAZ/SMAD4-induced Ddah1 transcription. Deletion of Ddah1 in osteoblast-lineage cells fails to respond to mechanical stimulus-associated bone formation. Taken together, the study reveals mechanical force is capable of down-regulating ADMA to enhance bone formation.

Metabolites of L-ARG in Exhaled Breath Condensate and Serum Are Not Biomarkers of Bronchial Asthma in Children.

(1) Background: L-arginine (L-ARG) and its metabolites are involved in some aspects of asthma pathogenesis (airway inflammation, oxidative stress, bronchial responsiveness, collagen deposition). Published data indicate that lungs are a critical organ for the regulation of L-ARG metabolism and that alterations in L-ARG metabolism may be significant for asthma. The aim of this study was to assess the levels of L-ARG and its metabolites in pediatric patients with asthma in serum and exhaled breath condensate (EBC) by mass spectrometric analysis and compare them with non-asthmatic children. (2) Methods: Sixty-five children (37 pediatric patients with bronchial asthma and 28 healthy control subjects) aged 6–17 participated in the study. All participants underwent a clinical visit, lung tests, allergy tests with common aeroallergens, and serum and EBC collection. The levels of biomarkers were determined in both serum and EBC. Analytical chromatography was conducted using an Acquity UPLC system equipped with a cooled autosampler and an Acquity HSS T3 column. Mass spectrometric analysis was conducted using the Xevo G2 QTOF MS with electrospray ionization (ESI) in positive ion mode. (3) Results: Asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) levels in serum and EBC did not differ significantly in asthmatic children and healthy control subjects. We found no correlation between forced expiratory volume in one second (FEV1) and L-ARG and its metabolites, as well as between interleukin-4 (IL-4) serum level and L-ARG and its metabolites. Concentrations of ADMA, SDMA, citrulline (CIT), and ornithine (ORN) were higher in serum than EBC in asthmatics and non-asthmatics. By contrast, concentrations of dimethylarginine (DMA) were higher in EBC than serum. ADMA/L-ARG, SDMA/L-ARG, and DMA/L-ARG ratios were significantly higher in EBC than in serum in asthmatics and in non-asthmatics. (4) Conclusions: Serum and EBC concentrations of L-ARG and its metabolites were not an indicator of pediatric bronchial asthma in our study.

The Functional Polymorphism of DDAH2 rs9267551 Is an Independent Determinant of Arterial Stiffness.

Background: The association of circulating asymmetric dimethylarginine (ADMA) levels with cardiovascular risk and arterial stiffness has been reportedly demonstrated, although the causal involvement of ADMA in the pathogenesis of these conditions is still debated. Dimethylaminohydrolase 2 (DDAH2) is the enzyme responsible for ADMA hydrolysis in the vasculature, and carriers of the polymorphism rs9267551 C in the 5′-UTR of DDAH2 have been reported to have higher DDAH2 expression and reduced levels of serum ADMA.Approach and Results: We genotyped rs9267551 in 633 adults of European ancestry and measured their carotid–femoral pulse wave velocity (cfPWV), the gold-standard method to estimate arterial stiffness. cfPWV resulted significantly lower in rs9267551 C allele carriers (Δ = −1.12 m/s, P < 0.01) after correction for age, sex and BMI, and a univariate regression showed that the presence of rs9267551 C variant was negatively associated with cfPWV (β = −0.110, P < 0.01). In a multivariable regression model, subjects carrying the rs9267551 C allele manifested significantly lower cfPWV than GG carriers (β = −0.098, P = 0.01) independently from several potential confounders. We measured circulating ADMA levels in a subset of 344 subjects. A mediation analysis revealed that the effect of DDAH2 rs9267551 genotype on cfPWV was mediated by the variation in ADMA levels.Conclusions: These evidences hint that the presence of rs9267551 C allele may explain, at least in part, a reduction in vessel rigidity as measured by cfPWV, and support the attribution of a causative role to ADMA in the pathogenesis of arterial stiffness.