Asymmetric Dimethyl Arginine Level in Children with Sickle Cell Disease: A Cross Sectional Study

Background: Sickle cell disease (SCD) consists of a group of hemoglobinopathies in which individuals inherit hemoglobin variants derived from single point mutations. Asymmetric dimethylarginine (ADMA) contributes to limiting Nitric Oxide (NO) bioavailability in SCD. The aim of the present study was to assess the level of the Asymmetric Dimethyl Arginine in children with sickle cell. Methods: This cohort cross-sectional study was carried out on 60 children which were divided in to 3 equal groups. Group I: SCD children with sickle retinopathy. Group II: SCD children without retinopathy. Group III: healthy control children who were selected from the outpatient clinic. Results: There was a significant increase in ADMA level among participants withSCD. There was a positive significant correlation between ADMA level and family history as well as the incidence of hepatomegaly. There was no significant correlation between ADMA level and demographic and laboratory parameters except LDH. Conclusions: The level of ADMA is elevated in children with sickle cell anemia. High plasma ADMA level is a risk for hepatomegaly in children with sickle cell anemia.

Effect of Vitamin D supplementation on symmetric dimethyl arginine, asymmetric dimethyl arginine, homocysteine levels in rats being exposed to gamma radiation

Background: Radiation causes to damage on endothelial cells by increasing oxidative stress. Vitamin D is also a potent anti-oxidant that facilitates balanced mitochondrial activities, preventing oxidative stress-related protein oxidation, lipid peroxidation, and DNA damage. Aims and Objective: We aimed to investigate the potential effect of vitamin D supplementation on levels of Hcy (homocysteine), ADMA (Asymmetric Dimethyl Arginine), and SDMA (Symmetrical Dimethyl Arginine) which are admitted as endothelial dysfunction markers in rat models that are exposed to gamma radiation. Materials and Methods: Twentyfour female Wistar Albino rats were selected for the study. The mean weight of these rats were between 200 and 250 grams. Rats were fed with standard light (12 hours day light /12 hours dark), enough water (ad-libitum) at temperature (25ºC) for a total of 4 weeks. The rats were divided into 4 different groups and each group consisted of 6 rats. controlgroup (group I) did not receive any supplementation and not expose to gamma radiation), Group II was merely exposed to gamma radiation, Group III was exposed to gamma radiation and received vitamin D supplementation, and Group IV merely received vitamin D supplementation. Groups that are given vitamin D supplementation were fed by oral gavage at the same time and every day for one week. Finally, Group II and Group III were exposed to gammaradiation at the 8th day. After the completion of all processes, Vitamin D, ADMA, SDMA and Hcy levels were measured by HPLC (High-performance liquid chromatography) method. Results: When the results of Group II and Group III were compared with each other, we achieved merely statistical significance in vitamin D results (p=0.04) but did not other parameters (p>0.05). Conclusion: We observed that vitamin D supplementation did not any effect on SDMA, ADMA, and Hcy that accompany possible endothelial dysfunction after gamma radiation exposure.

LC–MS/MS quantification of asymmetric dimethyl arginine and symmetric dimethyl arginine in plasma using surrogate matrix and derivatization with fluorescamine

Aim: A novel LC–MS/MS method using a surrogate matrix and derivatization with fluorescamine was developed and validated for simultaneous quantification of asymmetric dimethyl arginine and symmetric dimethyl arginine. Methods & results: Asymmetric dimethyl arginine, symmetric dimethyl arginine and corresponding internal standards were extracted using protein precipitation and derivatization with fluorescamine followed by SPE. Derivatives were analyzed by turbo ion spray LC–MS/MS in the positive ion mode. Methodology was successfully transferred across multiple preclinical species and utilized in the support of several investigative studies. Conclusion: A new LC–MS/MS analytical methodology that utilizes a surrogate matrix and derivatization with fluorescamine was successfully developed and validated.

Evaluation of homocystein and asymmetric dimethyl arginine levels in patients with coronary slow flow phenomenon

Background Previous studies have demonstrated that homocysteine and asymmetric dimethyl arginine (ADMA) levels were strongly associated with cardiovascular diseases including coronary artery disease. The aim of this study was to investigate the role of plasma homocysteine and ADMA levels in the pathogenesis of coronary slow flow (CSF) phenomenon. Methods Twenty-three patients with CSF and 25 controls with normal coronary flow were included in this study. The quantitative measurement of coronary blood flow was performed using the thrombolysis in myocardial infarction frame count method. Plasma homocysteine and ADMA levels were determined using enzymatic assays from venous blood samples. Results The patients with CSF had significantly higher plasma homocysteine levels than controls (16.2 ± 7.6 vs. 12.2 ± 2.2 μM/L; p = 0.023). The uric acid levels were significantly higher in CSF group than controls (5.4 ± 1.1 vs. 4.6 ± 0.9 mg/dl; p = 0.011). Plasma ADMA levels were also higher in the CSF group; however, this was not statistically significant (0.6 ± 0.1 vs. 0.5 ± 0.2 μM/L; p = 0.475). Conclusions Increased homocysteine and uric acid levels may play an important role in the pathogenesis of CSF. Further large scale studies are required to determine the relationship between ADMA levels and CSF.