Korean Circ J.  2006 Apr;36(4):285-291. 10.4070/kcj.2006.36.4.285.

Binding of Annexin V to Oxidized Lipid on Oxidatively Damaged Erythrocyte

• Lee KE
• Lee KH
• Choi YJ
• Lee KH
• Choi SH
• Lee SH
• Kim HJ
• Lee KJ
• Kim TH
• Ko HS
• Kim CJ
• Ryu WS

• KMID: 1859056
• DOI: http://doi.org/10.4070/kcj.2006.36.4.285

Abstract

BACKGROUND AND OBJECTIVES: Annexin V is known to bind to the phosphatidylserine (PS) of damaged cell membranes. We recently demonstrated that annexin V binds to oxidized red blood cells (oxRBC). The aim of this study was to find whether annexin V binds to oxidized lipids or to the PS of oxRBC.
MATERIALS AND METHODS
Red blood cells (RBC) were oxidized by the addition of CuSO4, and the degree of oxidation evaluated using the semiquantitative measurement of thiobarbituric acid reactive substance (TBARS). The binding of annexin V to oxRBC was evaluated by flow cytometry.
RESULTS
Annexin V was found to bind to oxRBC, but not to native RBC. The percentage of RBC binding to annexin V was closely correlated with the degree of oxidation, as measured using TBARS (r=0.99, p=0.000) in relation to the concentration of CuSO4. The binding of annexin V to oxRBC was attenuated in the presence of oxidized low density lipoprotein (oxLDL), with these phenomena also being dosedependent. The binding was reduced by 71.0+/-3.0% in the presence of 100 microgram/mL oxLDL. LDL had no influence on the binding of annexin V to oxRBC.
CONCLUSION
These findings suggest that annexin V may bind to the oxidized lipids of cell membranes. Further studies will be required to evaluate the relative importance between oxidized lipids and PS, and to find the characteristics of oxidized lipids in the binding of annexin V to damaged cell membranes.

Keyword

Erythrocytes; Low density lipoprotein; Lipid peroxidation; Annexin V; Binding

MeSH Terms

Annexin A5*
Cell Membrane
Erythrocytes*
Flow Cytometry
Lipid Peroxidation
Lipoproteins
Thiobarbituric Acid Reactive Substances
Annexin A5
Lipoproteins
Thiobarbituric Acid Reactive Substances