Influence of acetylsalicylate on plasma lysophosphatidic acid level in patients with ischemic cerebral vascular diseases

Background and purpose: Lysophosphatidic acid (LPA) is released from activated platelets. Acetylsalicylate (aspirin) is the most commonly used antiplatelet drug. The purpose of this study is to observe whether treatment with acetylsalicylate decreases the LPA level in patients with ischemic cerebrovascular diseases. Methods: We performed a study examining LPA level in fresh plasma in cases and controls enrolled in the LPA and Stroke Prevention Study. Level of LPA was assayed by measuring its inorganic phosphorus after separation by chromatography. Results: An elevated LPA level was seen in cases (n=254) with ischemic cerebrovascular disease (3.11 +/- 1.55 mmol/l) compared with 136 healthy controls (1.77 +/- 1.04 mmol/l) (p<0.001). Administration of aspirin (100 mg q.d.) for 1 month significantly lowered LPA level in patients (n=142) (2.41 +/- 1.03 mmol/l) compared with that before taking acetylsalicylate (4.06 +/- 1.03 mmol/l) (p<0.001). However, the LPA level in patients (n=36) who stopped acetylsalicylate after taking it for 1 month was re-elevated. Before and after taking acetylsalicylate for 1 month, their LPA levels were 4.23 +/- 1.15 and 1.93 +/- 0.85 mmol/l, respectively. After 1 month withdrawal, level was 3.90 +/- 1.09 mmol/l (p<0.001 compared that before taking acetylsalicylate). Conclusion: Our findings support a close association between increased plasma LPA level and platelet activation. Acetylsalicylate could decrease plasma LPA levels, which may be used as a mechanism for acetylsalicylate in the prevention of ischemic stroke.