TY - JOUR
T1 - Enhanced expression of Lp-PLA2 and lysophosphatidylcholine in symptomatic carotid atherosclerotic plaques
AU - Mannheim, Dallit
AU - Herrmann, Joerg
AU - Versari, Daniele
AU - Gössl, Mario
AU - Meyer, Fredric B.
AU - McConnell, Joseph P.
AU - Lerman, Lilach O.
AU - Lerman, Amir
PY - 2008/5/1
Y1 - 2008/5/1
N2 - BACKGROUND AND PURPOSE-: Circulating lipoprotein-associated phospholipase A2 (Lp-PLA2) has emerged as a novel biomarker for cardiovascular diseases. However, the correlation between the plaque expression of Lp-PLA2 and plaque oxidative stress, inflammation, and stability as well as the clinical presentation remains poorly defined, especially for cerebrovascular disease. Therefore, this study was performed to test the hypothesis that Lp-PLA2 expression is higher in symptomatic than in asymptomatic carotid plaques of patients undergoing carotid endarterectomy. METHODS-: The expression of Lp-PLA2 in 167 carotid artery plaques was determined by immunoblotting and immunostaining. Plaque oxidative stress, inflammation, and stability were quantified by NAD(P)H oxidase p67phox and MMP-2 immunoblotting, oxidized LDL (oxLDL) immunoreactivity, macrophage and Sirius red collagen staining. Lysophosphatidylcholine 16:0 (lysoPC) concentration was measured in 55 plaques using liquid chromatography tandem mass spectrometry. RESULTS-: Lp-PLA2 expression was significantly higher in plaques of symptomatic patients than asymptomatic patients (1.66±0.19 versus 1.14±0.10, P<0.05) and localized mainly to shoulder and necrotic lipid core areas in colocalization with oxLDL and macrophage content. Similarly, Lp-PLA2 expression was related to collagen content, which was lower in plaques from symptomatic patients than in plaques from asymptomatic patients (9.1±2.2 versus 18.5±1.7% of staining/field, P<0.001). LysoPC plaque concentration was significantly higher in plaques of symptomatic than asymptomatic patients (437.0±57.91 versus 228.84±37.00 mmol/L, P<0.05). CONCLUSIONS-: Symptomatic carotid artery plaques are characterized by increased levels of Lp-PLA2 and its product lysoPC in correlation with markers of tissue oxidative stress, inflammation, and instability. These findings strongly support a role for Lp-PLA2 in the pathophysiology and clinical presentation of cerebrovascular disease.
AB - BACKGROUND AND PURPOSE-: Circulating lipoprotein-associated phospholipase A2 (Lp-PLA2) has emerged as a novel biomarker for cardiovascular diseases. However, the correlation between the plaque expression of Lp-PLA2 and plaque oxidative stress, inflammation, and stability as well as the clinical presentation remains poorly defined, especially for cerebrovascular disease. Therefore, this study was performed to test the hypothesis that Lp-PLA2 expression is higher in symptomatic than in asymptomatic carotid plaques of patients undergoing carotid endarterectomy. METHODS-: The expression of Lp-PLA2 in 167 carotid artery plaques was determined by immunoblotting and immunostaining. Plaque oxidative stress, inflammation, and stability were quantified by NAD(P)H oxidase p67phox and MMP-2 immunoblotting, oxidized LDL (oxLDL) immunoreactivity, macrophage and Sirius red collagen staining. Lysophosphatidylcholine 16:0 (lysoPC) concentration was measured in 55 plaques using liquid chromatography tandem mass spectrometry. RESULTS-: Lp-PLA2 expression was significantly higher in plaques of symptomatic patients than asymptomatic patients (1.66±0.19 versus 1.14±0.10, P<0.05) and localized mainly to shoulder and necrotic lipid core areas in colocalization with oxLDL and macrophage content. Similarly, Lp-PLA2 expression was related to collagen content, which was lower in plaques from symptomatic patients than in plaques from asymptomatic patients (9.1±2.2 versus 18.5±1.7% of staining/field, P<0.001). LysoPC plaque concentration was significantly higher in plaques of symptomatic than asymptomatic patients (437.0±57.91 versus 228.84±37.00 mmol/L, P<0.05). CONCLUSIONS-: Symptomatic carotid artery plaques are characterized by increased levels of Lp-PLA2 and its product lysoPC in correlation with markers of tissue oxidative stress, inflammation, and instability. These findings strongly support a role for Lp-PLA2 in the pathophysiology and clinical presentation of cerebrovascular disease.
KW - Atherosclerosis
KW - Carotid
KW - Lp-PLA2
KW - Lysophosphatidylcholine
KW - Unstable plaque
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U2 - 10.1161/STROKEAHA.107.503193
DO - 10.1161/STROKEAHA.107.503193
M3 - Article
C2 - 18356547
AN - SCOPUS:44449157784
SN - 0039-2499
VL - 39
SP - 1448
EP - 1455
JO - Stroke
JF - Stroke
IS - 5
ER -