Extracellular phospholipases in atherosclerosis.
Sonia-Athina Karabina1, Sarah Gora, Rajai Atout
1INSERM UMRS 937, Université Pierre et Marie Curie UPMC-Paris 6, Faculté de Médecine Pierre et Marie Curie, 91 Boulevard de l'Hôpital, Paris 75634 Cedex 13, France.
Biochimie
|February 16, 2010
Summary
Phospholipases A2 (PLA2) enzymes are implicated in atherosclerosis. Specifically, Lp-PLA2 and PLA2GX play roles in lipoprotein metabolism and inflammation, influencing the development of atherosclerotic lesions.
Area of Science:
- Biochemistry
- Cardiovascular Biology
- Enzymology
Background:
- Phospholipases A2 (PLA2) are enzymes crucial for phospholipid metabolism.
- Plasma PAF-acetylhydrolase (PAF-AH), also known as Lp-PLA2, is linked to atherogenesis.
- Secreted PLA2 group X (PLA2GX) is a potential target in atherosclerosis research.
Purpose of the Study:
- To investigate the roles of Lp-PLA2 and PLA2GX in atherosclerosis.
- To understand the distribution and activity of these enzymes in relation to lipoproteins.
- To explore the therapeutic potential of targeting PLA2 enzymes in cardiovascular disease.
Main Methods:
- Analysis of enzyme activity in plasma and atherosclerotic lesions.
- Investigating enzyme association with lipoproteins (LDL, HDL).
- Utilizing genetic approaches to study enzyme function and polymorphisms.
Main Results:
- PAF-AH is associated with LDL and HDL, with altered activity in hypercholesterolemia.
- PLA2GX is present in atherosclerotic lesions and promotes macrophage foam cell formation.
- A PLA2GX polymorphism (Arg38Cys) results in a catalytically inactive enzyme.
Conclusions:
- Extracellular PLA2 enzymes, particularly Lp-PLA2 and PLA2GX, are involved in atherosclerosis.
- PLA2GX may play a significant role in regulating PAF and promoting foam cell formation.
- Further research is needed to elucidate the precise roles of extracellular PLA2s in cardiovascular disease progression.
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