Scientific Journal of

  Abstract

 Background and Objectives

 There are several evidences that show lipoproteins especially Low Density Lipoprotein (LDL) and platelets play an important role in the pathogenesis of atherosclerotic plaque and thrombosis. The important issue is how lipids induce primary clot formation and detect primary thrombosis.

 Materials and Methods

 The present cross-sectional study evaluated 42 of hyper-cholesterolmias who had serum cholesterol levels above the normal range (200 mg/dL based on the Iranian serum cholesterol reference) and 14 healthy volunteers as the normal control. The serum LDLs of the samples were isolated and oxidized then, the function of platelet after being affected by natural LDL (N-LDL) and oxidized LDL (OX-LDL) was observed. Finally, the data were statistically analyzed using SPSS version 16 software and the student T-test.

 Results

 The serum ox-LDL was detected in 234 nm, the absorbance from 0.45 in LDL turned to 0.98 in OX-LDL, (p < 0.0008). Results in our study indicated that, in contrary to N-LDL, OX-LDL induced increased platelet aggregation in aggregometry method, respectly 11% platelet agggragation with N-LDL and 45% with OX-LDL. Flowcytometry analysis of platelet function indicated that in the vicinity of N-LDL confirm the only 8% of platelets were binding with fibrinogen, whereas 82% of platelets binding with 20 mg/mL of OX-LDL.

 Conclusions

 The study shows that LDLs modified by serum lipooxidants and exposed to OX-LDL may induce platelet activity and aggregation followed by the increase risk of thrombosis and cardiovascular diseases.