Relationship between obesity, smoking, and the endogenous nitric oxide synthase inhibitor, asymmetric dimethylarginine.

Center for Clinical Research, Ullevaal University Hospital, NO-0407 Oslo, Norway.
Metabolism (Impact Factor: 3.1). 12/2004; 53(12):1574-9. DOI: 10.1016/j.metabol.2004.06.026
Source: PubMed

ABSTRACT We investigated the levels of asymmetric dimethylarginine (ADMA), an important endogenous inhibitor of nitric oxide (NO), as related to metabolic risk factors known to contribute to atherosclerotic disease. Dimethylarginines were analysed in a cross-sectional study of 563 elderly high-risk men (70 +/- 6 years). ADMA and the l-arginine/ADMA (l-arg/ADMA) ratio were highly significantly correlated with several metabolic risk factors. However, only the association with body mass index (BMI) remained significant after adjustment for inter-related variables. When analyzing the results according to being overweight or not, ADMA levels were independently significantly higher (P = .05) and the L-arg/ADMA ratios were significantly lower (P < .008) in individuals with high BMI (> or =26 kg/m(2), median value) as compared with subjects with low BMI. ADMA levels were furthermore significantly lower (P = .037) and L-arginine and the l-arg/ADMA ratios were significantly higher (P = .004 and P = .001, respectively) in smokers compared with nonsmokers, the latter being independent of other risk factors. The strong relationship found between BMI and plasma levels of ADMA and the l-arg/ADMA ratio indicate a link to endothelial dysfunction in overweight subjects. The beneficial dimethylarginine profile observed in smokers in this elderly population is not easily explainable and should be further investigated.

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    ABSTRACT: Asymmetric dimethylarginine (ADMA) is an endogenous competitive inhibitor of nitric oxide (NO) synthase, an enzyme responsible for the generation of NO. Plasma concentrations of ADMA increase in the elderly and in postmenopausal women. In fact, an elevated ADMA level is a risk factor of cardiovascular disease. Aerobic exercise has a beneficial effect on cardiovascular disease. However, the relationship between ADMA and aerobic fitness is unknown. The aim of this study was to determine whether plasma ADMA concentrations correlate with aerobic fitness levels in postmenopausal women. Thirty healthy postmenopausal women aged 50-76 years participated in this study. We measured plasma concentrations of ADMA and oxygen consumption at the ventilatory threshold (VO2VT) as an index of aerobic fitness. Subjects were divided into the low aerobic fitness (Low fitness) and high aerobic fitness (High fitness) groups, and the dividing line was set at the median VO2VT value. VO2VT was significantly higher in the High fitness group than in the Low fitness group (P<0.01). The plasma ADMA concentrations in the High fitness group were significantly lower than those in the Low fitness group (P<0.05). There was a negative correlation between plasma ADMA concentrations and VO2VT (r=-0.532, P<0.01). We found that plasma ADMA concentrations were associated with aerobic fitness in postmenopausal women. The results of this study suggest that habitual aerobic exercise may decrease plasma ADMA concentrations.
    Life sciences 05/2014; · 2.56 Impact Factor
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    ABSTRACT: Circulating asymmetrical dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthesis, has been proposed as a biomarker for clinical outcome. Dimethylarginine dimethylaminohydrolase (DDAH) is the main enzyme responsible for ADMA metabolism and elimination. Adipose tissue ADMA concentrations and DDAH activity and their role in diabetes and obesity have not yet been investigated. In this study, we evaluated clinical microdialysis in combination with a sensitive analytical method (GC-MS/MS) to measure ADMA concentrations in extracellular fluid. Adipose tissue ADMA concentrations were assessed before and during an oral glucose tolerance test in lean healthy subjects and subjects with diabetes (n = 4 each), and in morbidly obese subjects before and after weight loss of 30 kg (n = 7). DDAH activity was determined in subcutaneous and visceral adipose tissue obtained during laparoscopic surgery (n = 5 paired samples). Mean interstitial ADMA concentrations did not differ between study populations (healthy 0.17 ± 0.03 µM; diabetic 0.21 ± 0.03 µM; morbidly obese 0.16 ± 0.01 and 0.17 ± 0.01 µM before and after weight loss, respectively). We did not observe any response of interstitial ADMA concentrations to the oral glucose challenge. Adipose tissue DDAH activity was negligible compared to liver tissue. Thus, adipose tissue ADMA plays a minor role in NO-dependent regulation of adipose tissue blood flow and metabolism.
    International Journal of Molecular Sciences 01/2014; 15(1):1189-1200. · 2.46 Impact Factor
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    ABSTRACT: Background Asymmetric dimethylarginine (ADMA) has recently been investigated as a risk marker for cardio- and cerebrovascular diseases. However, whether ADMA levels are related to the risk of stroke in the Japanese general population remains unclear. Methods We examined 769 Japanese men (mean age, 47 ± 5 years) undergoing health examinations. Each subject’s ADMA level and various vascular risk factors were assessed; the predicted 10-year stroke risk was calculated using the point-based prediction model from the Japan Public Health Center study. Results In a multiple linear regression analysis, age, body mass index, estimated glomerular filtration rate, and current smoking status were significant independent determinants of ADMA levels. A significant odds ratio (OR) for high predicted stroke risk (10-year risk ≥ was noted in the highest quartile of ADMA levels (OR, 2.47; 95% CI, 1.002–6.07), compared with the lowest quartile, after adjusting for potential confounding factors. A significant OR for high predicted stroke risk was also found for each standard deviation increment in ADMA level (adjusted OR, 1.46; 95% CI, 1.10–1.92). Conclusion Elevated ADMA levels were significantly associated with an increased predicted stroke risk, suggesting that measuring ADMA levels may be useful for identifying middle-aged Japanese men with a high risk of stroke.
    Journal of the neurological sciences 01/2013; · 2.32 Impact Factor