Evaluation of NPP1 as a Novel Biomarker of Coronary Artery Disease: A Pilot Study in Human Beings

Purpose: Coronary artery calcification (CAC) is utilized as an important tool for global risk assessment of cardiovascular events in individuals with intermediate risk. Ecto phosphodiesterase/nucleotide phosphohydrolase-1(ENPP1) converts extracellular nucleotides into inorganic pyrophosphate and it is a key regulator of tissue calcification that adjusts calcification in tissues like vascular smooth muscle cells. The main purpose of this clinical study was to find out the correlation between ENPP1 serum concentration and CAC in human for the first time. Methods: In this study 83 patients (16 diabetic patients and 67 non-diabetic patients) with coronary artery disease who fulfilled inclusion and exclusion criteria, entered the study. For all patients a questionnaire consisting demographic data and traditional cardiovascular risk factors were completed. Computed tomography (CT)-Angiography was carried out to determine coronary artery calcium score and enzyme-linked immunosorbent assay (ELISA) method was used for measuring ENPP1 serum concentrations. Results: There was a reverse significant correlation between ENPP1 serum concentration and total CAC score and also CAC of right coronary artery (RCA) (P<0.05) in non-diabetic patients. Conclusion: On the basis of our results, ENPP1 serum concentration may be a suitable biomarker for coronary artery disease at least in non-diabetic patients. However, more studies with higher sample size are necessary for its confirmation.