Relationship between levels of Annexin A1, lipoprotein-associated phospholipase A2 and Bax and human carotid atherosclerotic plaques

Objective To investigate the correlation between levels of Annexin A1,Bax and lipoprotein-associated phospholipase A2 (Lp-PLA2) and both formation and stability of human carotid atherosclerotic plaques.Methods Forty-five specimens from patients with carotid atherosclerotic plaques (test group,group A),admitted to our hospital from May 2010 to June 2011 and performed carotid endarterectomy (CEA),and 20 specimens from patients with mesenteric artery and 20 healthy subjects (control groups,group B and group C,respectively) were collected in our study.The carotid atherosclerotic plaque specimens were divided into soft plaque group A1 (n=15),mixed plaque group A2 (n=15) and hard plaque group A3 (n=15) according to the results of carotid artery ultrasound.The Lp-PLA2 level in group A and group C was measured by enzyme linked immunosorbent assay (ELISA),and the mRNA and protein expressions of Annexin A1 and Bax in group A and group B were determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting.Results The level of Lp-PLA2 in all patients with carotid atherosclerotic plaques was significantly increased as compared with that in group C (P＜0.05); that in group A1 was significantly higher than that in group A3 (P＜0.05).The mRNA and protein expressions of Annexin A1 and Bax in all patients with carotid atherosclerotic plaques were significantly increased as compared with those in group B (P＜0.05); group A1 exhibited lower mRNA and protein expressions of Annexin A1 than group A3 (P＜0.05),while group A1 exhibited higher mRNA and protein expressions of Bax than group A3 (P＜0.05).Conclusion Annexin A1,Lp-PLA2 and Bax participate in the formation and stability of human carotid atherosclerotic plaques. Key words: Annexin A1; Lipoprotein-associated phospholipase A2; Bax; Human carotid atherosclerotic plaque