phosphothreonine and Calcinosis

Calcific Aortic Valve Disease (CAVD) is an active pathological process leading to biomineralization of the aortic cusps. We characterized circulating and tissue Osteopontin (OPN) as a biomarker for CAVD.. Here we investigate the post-translational modifications of circulating OPN and correlate the phosphorylation status with the ability to prevent calcification.. Circulating OPN levels were estimated in CAVD patients (n = 51) and controls (n = 56). In a subgroup of 27 subjects, OPN was purified and the phosphorylation status analyzed.. Plasma OPN levels were significantly elevated in CAVD patients as compared to the controls and correlates with the aortic valve calcium score. Our study demonstrates that phospho-threonine levels of OPN purified from controls were higher when compared to CAVD subjects, whereas phospho-serine and phospho-tyrosine levels were comparable between the two groups.. The dephosphorylation of circulating OPN correlates with severe valvular calcification in patients with CAVD.

Topics: Aged; Aged, 80 and over; Aortic Valve; Aortic Valve Stenosis; Biomarkers; Calcinosis; Calcium; Case-Control Studies; Female; Humans; Male; Osteopontin; Phosphorylation; Phosphothreonine; Protein Processing, Post-Translational; Severity of Illness Index