Proteomic analysis of plasma-purified VLDL, LDL, and HDL fractions from atherosclerotic patients undergoing carotid endarterectomy: identification of serum amyloid A as a potential marker.
Apolipoproteins are very heterogeneous protein family, implicated in plasma lipoprotein structural stabilization, lipid metabolism, inflammation, or immunity. Obtaining detailed information on apolipoprotein composition and structure may contribute to elucidating lipoprotein roles in atherogenesis and to developing new therapeutic strategies for the treatment of lipoprotein-associated disorders. This study aimed at developing a comprehensive method for characterizing the apolipoprotein component of plasma VLDL, LDL, and HDL fractions from patients undergoing carotid endarterectomy, by means of two-dimensional electrophoresis (2-DE) coupled with Mass Spectrometry analysis, useful for identifying potential markers of plaque presence and vulnerability. The adopted method allowed obtaining reproducible 2-DE maps of exchangeable apolipoproteins from VLDL, LDL, and HDL. Twenty-three protein isoforms were identified by peptide mass fingerprinting analysis. Differential proteomic analysis allowed for identifying increased levels of acute-phase serum amyloid A protein (AP SAA) in all lipoprotein fractions, especially in LDL from atherosclerotic patients. Results have been confirmed by western blotting analysis on each lipoprotein fraction using apo AI levels for data normalization. The higher levels of AP SAA found in patients suggest a role of LDL as AP SAA carrier into the subendothelial space of artery wall, where AP SAA accumulates and may exert noxious effects.
Dipartimento di Scienze Biomediche, University of Sassari, Via Muroni 25, 07100 Sassari, Italy.
Antonio J
AJ
Lepedda
Dipartimento di Scienze Biomediche, University of Sassari, Via Muroni 25, 07100 Sassari, Italy.
Gabriele
G
Nieddu
Dipartimento di Scienze Biomediche, University of Sassari, Via Muroni 25, 07100 Sassari, Italy.
Elisabetta
E
Zinellu
Dipartimento di Scienze Biomediche, University of Sassari, Via Muroni 25, 07100 Sassari, Italy.
Pierina
P
De Muro
Servizio di Chirurgia Vascolare, Clinica Chirurgica Generale, University of Sassari, Viale S. Pietro 43/B, 07100 Sassari, Italy.
Franco
F
Piredda
Centro Cardiologico "F. Monzino," IRCCS, University of Milan, Via Carlo Parea 4, 20138 Milan, Italy.
Anna
A
Guarino
Centro Cardiologico "F. Monzino," IRCCS, University of Milan, Via Carlo Parea 4, 20138 Milan, Italy.
Rita
R
Spirito
Nurex S.r.l., Via Predda Niedda Strada 3, 07100 Sassari, Italy.
Franco
F
Carta
Dipartimento di Genetica, Biologia, Biochimica, University of Turin, Via Santena 19, 10126 Turin, Italy.
Francesco
F
Turrini
Dipartimento di Scienze Biomediche, University of Sassari, Via Muroni 25, 07100 Sassari, Italy.
Marilena
M
Formato
D001053:Apolipoproteins / Q000097:blood / Q000737:chemistry; D050197:Atherosclerosis / Q000097:blood* / Q000601:surgery; D015415:Biomarkers / Q000097:blood; D015153:Blotting, Western; D016022:Case-Control Studies; D016894:Endarterectomy, Carotid; D005260:Female; D006801:Humans; D008075:Lipoproteins, HDL / Q000097:blood*; D008077:Lipoproteins, LDL / Q000097:blood*; D008079:Lipoproteins, VLDL / Q000097:blood*; D008297:Male; D040901:Proteomics / Q000379:methods*; D000685:Serum Amyloid A Protein / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013347:Subcellular Fractions / Q000378:metabolism
D001053:Apolipoproteins; D015415:Biomarkers; D008075:Lipoproteins, HDL; D008077:Lipoproteins, LDL; D008079:Lipoproteins, VLDL; D000685:Serum Amyloid A Protein