Risk of cardiovascular diseases in diabetes mellitus and serum concentration of asymmetrical dimethylarginine

Asymmetric dimethylarginine and gestational diabetes mellitus: a systematic review and meta-analysis

PURPOSE

Emerging evidence demonstrates that asymmetric dimethylarginine (ADMA) levels are elevated in patients with or at risk of cardiovascular disease (CVD). Since women with gestational diabetes mellitus (GDM) are at high risk of future CVD, we conducted a systematic review and meta-analysis to compare ADMA concentrations between women with and without GDM during pregnancy and postpartum.

METHODS

PubMed, Google Scholar, EMBASE, and CINAHL databases were searched. The review protocol is registered in PROSPERO (CRD42021276796). Study selection, data extraction, and data analyses were performed in accordance with PRISMA guidelines. Random-effects model was used to quantify ADMA levels in the study groups.

RESULTS

Eleven studies provided data on 1148 women. Mean plasma ADMA concentration was 0.04 μmol/L (95% confidence interval (CI) -0.06-0.15) higher in pregnant women with GDM than those without GDM, but no significant difference was observed. In contrast, our meta-analysis demonstrated a significant increase in postpartum mean ADMA concentration (Mean Difference (MD) 0.11 μmol/L; 95% CI 0.05-0.16) among women with previous GDM compared to women without previous GDM.

CONCLUSION

Elevated ADMA levels in GDM may be a CVD risk factor, suggesting that ADMA may be a potential biomarker for early CVD risk prediction in women with GDM.

The impact of type 2 diabetes duration on serum asymmetric dimethylarginine and C-reactive protein concentration in Bosnian patients

Objective. The present study assessed the impact of type 2 diabetes mellitus (T2DM) duration on the serum asymmetric dimethylarginine (ADMA) and C-reactive protein (CRP) concentration in Bosnian patients.

Methods. Participants for this cross-sectional study were randomly selected from the Family Medicine Clinic (Sarajevo, Bosnia and Herzegovina). Serum ADMA concentration was determined by ELISA. Serum high-sensitivity (hs-CRP) was determined by particle-enhanced immunonephelometry. ANOVA test followed by Scheffe post-hoc test or Kruskal-Wallis test followed by Man-Whitney test were used for statistical analysis.

Results. The study included 38 patients in up to 10 years diabetes duration (≤10 years T2DM) group, 22 patients in greater than 10 years diabetes duration (>10 years T2DM) group, and 60 controls. Serum ADMA concentration in the >10 years T2DM group (1.81±0.15 μmol/L) was significantly higher compared to serum ADMA concentration in the ≤10 years T2DM group (1.38±0.41 μmol/L; p<0.001) and in controls (0.62±0.15 μmol/L; p<0.001). A significant difference in serum ADMA concentration was found between the <10 years T2DM group and the controls (p<0.001). The serum CRP concentration in the >10 years T2DM group [5.95 (4.20–9.12) mg/L] was significantly higher compared to serum CRP concentration in the <10 years T2DM group [2.35 (1.40–4.30) mg/L; p<0.001] and controls [0.85 (0.50–1.30) mg/L; p<0.001]. Significant difference in serum CRP concentration was observed between the <10 years T2DM group and controls (p<0.001).

Conclusions. The present study showed an increase in the serum ADMA and CRP concentrations with the advancement of T2DM. These results suggest that ADMA and CRP may serve as indicators of endothelial dysfunction and chronic low-grade inflammation progression in patients with T2DM. Larger prospective studies are required to confirm the observed findings.

Piper sarmentosum Promotes Endothelial Nitric Oxide Production by Reducing Asymmetric Dimethylarginine in Tumor Necrosis Factor-α-Induced Human Umbilical Vein Endothelial Cells

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial nitric oxide synthase (eNOS). ADMA is degraded by dimethylarginine dimethylaminohydrolase (DDAH). Elevated levels of ADMA lead to reduction in nitric oxide (NO) production, which is linked to endothelial dysfunction and atherosclerosis. Piper sarmentosum is an herb that has shown stimulation on endothelial NO production by increasing both expression and activity of eNOS. Thus, this study determined whether the positive effect of P. sarmentosum on NO production is related to its modulation on the DDAH-ADMA pathway in cultured human umbilical vein endothelial cells (HUVEC) exposed to tumor necrosis factor-α (TNF-α). HUVEC were divided into four groups: control, treatment with 250 µg/ml of aqueous extract of P. sarmentosum leaves (AEPS), treatment with 30 ng/ml of TNF-α, and concomitant treatment with AEPS and TNF-α for 24 h. After treatments, HUVEC were collected to measure DDAH1 messenger RNA (mRNA) expression using quantitative real-time polymerase chain reaction. DDAH1 protein level was measured using enzyme-linked immunosorbent assay (ELISA), and DDAH enzyme activity was measured using colorimetric assay. ADMA concentration was measured using ELISA, and NO level was measured using Griess assay. Compared to control, TNF-α-treated HUVEC showed reduction in DDAH1 mRNA expression (P < 0.05), DDAH1 protein level (P < 0.01), and DDAH activity (P < 0.05). Treatment with AEPS successfully increased DDAH1 mRNA expression (P < 0.05), DDAH1 protein level (P < 0.01), and DDAH activity (P < 0.05) in TNF-α-treated HUVEC. Treatment with TNF-α caused an increase in ADMA level (P < 0.01) and a decrease in endothelial NO production (P < 0.001). Whereas treatment with AEPS was able to reduce ADMA level (P < 0.01) and restore NO (P < 0.001) in TNF-α-treated HUVEC. The results suggested that AEPS promotes endothelial NO production by stimulating DDAH activity and thus reducing ADMA level in TNF-α-treated HUVEC.

Hemostasis, endothelial stress, inflammation, and the metabolic syndrome

Obesity and the metabolic syndrome (MS) are two of the pressing healthcare problems of our time. The MS is defined as increased abdominal obesity in concert with elevated fasting glucose levels, insulin resistance, elevated blood pressure, and plasma lipids. It is a key risk factor for type 2 diabetes mellitus (T2DM) and for cardiovascular complications and mortality. Here, we review work demonstrating that various aspects of coagulation and hemostasis, as well as vascular reactivity and function, become impaired progressively during chronic ingestion of a western diet, but also acutely after meals. We outline that both T2DM and cardiovascular disease should be viewed as inflammatory diseases and describe that chronic overload of free fatty acids and glucose can trigger inflammatory pathways directly or via increased production of ROS. We propose that since endothelial stress and increases in platelet activity precede inflammation and overt symptoms of the MS, they are likely the first hit. This suggests that endothelial activation and insulin resistance are probably causative in the observed chronic low-level metabolic inflammation, and thus both metabolic and cardiovascular complications linked to consumption of a western diet.

Levels of asymmetric dimethylarginine (ADMA), an endogenous nitric oxide synthase inhibitor, and risk of coronary artery disease: A meta-analysis based on 4713 participants

BACKGROUND

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial nitric oxide synthase by competing with L-arginine. As a result, the expression of nitric oxide decreases and endothelial dysfunction occurs. Studies have evaluated the association between the serum ADMA level and risk of coronary artery disease. However, conflicting results have been obtained.

METHODS

Pubmed, Web of Science, Embase, Ovid, Cochrane databases were searched to identify eligible studies published in English until December 2014. Association was assessed on the basis of weighted mean differences (WMD) with 95% confidence intervals (CIs). Publication bias was analysed using Begg's and Egger's tests. Sensitivity analysis was performed to evaluate result stability.

RESULTS

A total of 16 case-control studies with 2939 patients and 1774 controls were included in the meta-analysis. Pooled result indicated that patients with coronary artery disease yielded a higher ADMA level than healthy controls (WMD: 0.248, 95% CI: 0.156-0.340; p = 1.16 e-7). Sensitivity analysis suggested that our meta-analysis result was stable. Subgroup analysis found a similar pattern in patients with myocardial infarction (WMD: 0.397, 95% CI: 0.112-0.683; p = 0.0106), stable angina pectoris (WMD: 0.197, 95% CI: 0.031-0.364; p = 0.02) and unstable angina pectoris (WMD: 0.857, 95% CI: 0.293-1.420; p = 0.003).

CONCLUSIONS

Meta-analysis results indicated that an increased ADMA level is associated with an increased risk of coronary artery disease.

Asymmetric dimethylarginine and long-term adverse cardiovascular events in patients with type 2 diabetes: relation with the glycemic control

Background and aims

Elevated plasma asymmetric dimethylarginine (ADMA) levels have been observed in patients with insulin resistance and diabetes, and have been reported to predict adverse cardiovascular events in type 2 diabetic patients. However, the relationship between ADMA and glycemic control in patients with type 2 diabetes remained controversial.

Methods and results

We evaluated 270 patients with type 2 diabetes and measured their plasma ADMA and hemoglobin A1c (HbA1c) levels by high performance liquid chromatography. The mean age was 67 ± 12 years. The mean plasma ADMA and HbA1c level were 0.46 ± 0.09 μmol/l and 7.8 ± 1.6%, respectively. There was no significant correlation between plasma ADMA level and HbA1c level (r = −0.09, p = 0.13). During the median follow-up period of 5.7 years (inter-quartile range: 5.0 − 7.3 years), major adverse cardiovascular event (MACE, including cardiovascular death, myocardial infarction and stroke) was observed in 55 patients (20.4%). Multivariate Cox regression analysis revealed that the ADMA tertile was an independent risk factor for MACE (ADMA tertile III versus ADMA tertile I: p = 0.026, HR: 2.31, 95% CI: 1.10 − 4.81). The prognosis predictive power of ADMA disappeared in patients with well glycemic control (HbA1c ≤6.5%), and the ADMA-HbA1c interaction p value was 0.01.

Conclusions

In patients with type 2 diabetes, ADMA might be an independent risk factor for long-term adverse cardiovascular events. However, ADMA was not correlated with serum HbA1c level, and in diabetic patients with HbA1c ≤6.5%, elevated ADMA level was no longer associated with increased risk of long-term prognosis. Our findings suggested that the prognosis predictive value of ADMA in type 2 diabetes might be modified by the glycemic control.