Lipocalin-type prostaglandin D synthase is not a biomarker of atherosclerotic manifestations

Abstract

Objective. Over the last decades Lipocalin-type prostaglandin D synthase (L-PGDS), Osteoprotegerin (OPG), Osteopontin (OPN) and Pregnancy associated plasma protein A (PAPP-A) have been reported to be associated with coronary artery disease, and L-PGDS has been proposed as a potential new diagnostic tool in the setting of stable coronary artery disease. We set out to investigate if measurement of concentrations of these biomarkers could be used to differentiate between four groups of individuals with different atherosclerotic manifestations. Methods. A total of 120 individuals from four equal gender- and age-matched groups were studied: (i) no previous cardiovascular disease (CVD) and no coronary calcifications [CAC-negative group], (ii) no previous CVD but evidence of severe coronary calcifications [CAC-positive group], (iii) acute coronary syndrome [ACS-group], and (iv) clinical stable patients with CVD, who were referred for cardiovascular surgery [CVD-group]. Concentrations of L-PGDS, OPG, OPN and PAPP-A were analyzed and compared between the four groups. Results. We did not find any significant differences in L-PGDS concentrations between the four groups (p = 0.32). OPG concentrations differed significantly (p = 0.003), with the highest concentration observed in ACS patients. Considering OPN (p = 0.12) and PAPP-A (p = 0.53) their concentrations between groups did not differ significantly. Conclusion. The main message from this study is the observation that L-PGDS based on a single blood test appears to be less valuable than previously proposed in identification of patients with coronary artery disease. However, ACS patients have higher OPG concentrations than patients with different manifestations of stable atherosclerosis. Neither OPN nor PAPP-A concentrations differed between groups.

Key Words::

• Atherosclerosis
• coronary artery disease
• osteopontin
• osteoprotegerin
• PAPP-A

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

This study has been financially supported by the Danish Heart Association; the University of Southern Denmark, Odense, Faculty of Health Sciences; the Region of Southern Denmark; Odense University Hospital; Professor Torben Haghfelts fond til fremme af kardiologien, Denmark; Beckett-Fonden, Denmark; Direktør Kurt Bønnelycke og hustru fru Grethe Bønnelyckes Fond, Denmark; Tømrermester Alfred Andersen og Hustrus Fond, Denmark; Guldsmed A.L. & D. Rasmussen Mindefond, Denmark and Bønnelykkefonden, Denmark. A financial aid with a total grant number of 16.072 EURO was received for this and two other studies making it possible to pay the biochemical analyses.