Biomaterial Database

Phospholipase A2 modification enhances lipoprotein(a) binding to the subendothelial matrix. 1998

J Hoover-Plow, and A Khaitan, and G M Fless

Joseph J. Jacobs Center for Thrombosis and Vascular Biology, Department of Molecular Cardiology, The Cleveland Clinic Foundation, Ohio 44195, USA.

Lipoprotein(a), Lp(a), is found in the extracellular matrix in atherosclerotic plaques, but with a different localization than LDL. A two-compartment system, with a monolayer of endothelial cells forming a barrier, was used to compare the transport, cell binding, and retention of Lp(a) and LDL into the subendothelial matrix. Baseline values for transport and retention of Lp(a) and LDL were not significantly different. Incubation with lipoprotein lipase or sphingomyelinase caused modest and similar increases in transport and retention of the two lipoproteins. In contrast, incubation with phospholipase A2 (PLA2) resulted in a marked (4-fold) increase in retention of Lp(a) on the subendothelial matrix, but a lesser (2-fold) increase in LDL retention. Moreover, PLA2 treatment of Lp(a) enhanced its binding to individual matrix proteins (fibronectin, laminin, or collagen) by 4-10 times above that of LDL. The enzymatic activity of PLA2 was responsible for its effect on Lp(a) binding. The lysine binding sites of Lp(a) contributed to the increased binding of PLA2-modified Lp(a) to the matrix, and the enhanced lysine binding functions of PLA2-modified Lp(a) was demonstrated by two independent approaches. Thus, PLA2 modification leads to enhanced interactions of lipoproteins with the extracellular matrix, and this effect is more pronounced with Lp(a).

UI	MeSH Term	Description	Entries
D010741	Phospholipases A	Phospholipases that hydrolyze one of the acyl groups of phosphoglycerides or glycerophosphatidates.
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D004730	Endothelium, Vascular	Single pavement layer of cells which line the luminal surface of the entire vascular system and regulate the transport of macromolecules and blood components.	Capillary Endothelium,Vascular Endothelium,Capillary Endotheliums,Endothelium, Capillary,Endotheliums, Capillary,Endotheliums, Vascular,Vascular Endotheliums
D005109	Extracellular Matrix	A meshwork-like substance found within the extracellular space and in association with the basement membrane of the cell surface. It promotes cellular proliferation and provides a supporting structure to which cells or cell lysates in culture dishes adhere.	Matrix, Extracellular,Extracellular Matrices,Matrices, Extracellular
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D016326	Extracellular Matrix Proteins	Macromolecular organic compounds that contain carbon, hydrogen, oxygen, nitrogen, and usually, sulfur. These macromolecules (proteins) form an intricate meshwork in which cells are embedded to construct tissues. Variations in the relative types of macromolecules and their organization determine the type of extracellular matrix, each adapted to the functional requirements of the tissue. The two main classes of macromolecules that form the extracellular matrix are: glycosaminoglycans, usually linked to proteins (proteoglycans), and fibrous proteins (e.g., COLLAGEN; ELASTIN; FIBRONECTINS; and LAMININ).	Extracellular Matrix Protein,Matrix Protein, Extracellular,Matrix Proteins, Extracellular,Protein, Extracellular Matrix,Proteins, Extracellular Matrix