Circulating Cell Free Mitochondrial DNA is a Biomarker in the Development of Coronary Heart Disease in the Patients with Type 2 Diabetes.

BACKGROUND: Circulating cell-free mtDNA (ccf-mtDNA) is presumably derived from injured tissue or cells in the body and has been suggested to be a potential biomarker in several diseases. In the present study, we investigated whether ccf-mtDNA levels could serve as a biomarker of diabetic patients without Coronary Heart Disease (CHD) and correlate with their incidence to develop CHD.
METHODS: Ccf-mtDNA levels in plasma and the traditional CHD risk factors were determined in 50 type 2 diabetes (DM) with CHD and 50 DM without CHD patients and 50 age- and sex-matched healthy controls. MtDNA levels were assessed by measuring the NADH dehydrogenase 1 gene using quantitative real-time PCR. ROC curve analyses of plasma mtDNA in DM with or without CHD were also determined. Multivariate logistic regression analyses were conducted to determine the correlation between the mtDNA levels and traditional CHD risk factors.
RESULTS: The plasma ccf-mtDNA levels and CRP were significantly elevated in DM compared with healthy controls, and a consistent increase of mtDNA in diabetes with CHD compared to those without CHD. The area under the ROC curves of mtDNA in DM patients versus DM patients with CHD and healthy controls was 0.843 and 0.898, respectively. Correlation analyses showed that the mtDNA levels were significantly correlated with that of C-reactive protein (CRP) in patients with CHD.
CONCLUSIONS: Ccf-mtDNA was elevated in type 2 diabetes with CHD and correlated with CRP levels. Both may be considered a prognostic biomarker of CHD development.