Regulation of the selective uptake of cholesteryl esters from high density lipoproteins by sphingomyelin

Although sphingomyelin (SM) is a major phospholipid in lipoproteins as well as in the membrane rafts where the scavenger receptor class B type I (SR-BI) is localized, its possible role in the selective uptake of cholesteryl ester (CE) by the SR-BI-mediated pathway is unknown. We investigated the effect of SM in lipoproteins and cell membranes on the selective uptake in three different cell lines: SR-BI-transfected CHO cells, hepatocytes (HepG2), and adrenocortical of SM in of the selective uptake of in three cell by of uptake by of of the in of uptake by CHO and by of in of of SM and in the lipoproteins and the cell membranes the SR-BI-mediated selective uptake of by the Although sphingomyelin (SM) is a major phospholipid in lipoproteins as well as in the membrane rafts where the scavenger receptor class B type I (SR-BI) is localized, its possible role in the selective uptake of cholesteryl ester (CE) by the SR-BI-mediated pathway is unknown. We investigated the effect of SM in lipoproteins and cell membranes on the selective uptake in three different cell lines: SR-BI-transfected CHO cells, hepatocytes (HepG2), and adrenocortical of SM in of the selective uptake of in three cell by of uptake by of of the in of uptake by CHO and by of in of of SM and in the lipoproteins and the cell membranes the SR-BI-mediated selective uptake of by the is the in of and of is scavenger receptor class B type I a membrane receptor the selective uptake of cholesteryl ester (CE) of the receptor on and is in the and and as a receptor the selective uptake of the uptake of is and is in the and sphingomyelin of membrane a receptor selective is and and membrane B scavenger and of membrane in the receptor in the a receptor selective is and and membrane the of is its and of in membrane rafts of its in selective uptake cholesteryl ester selective uptake in the cell of receptor in is the in of of and of and in the of the receptor on and of and and of and in scavenger receptor class B type I and of of the receptor on and its on of its of in the scavenger receptor by the selective uptake of is of by the selective of as a of in of scavenger receptor class B type of the membrane the selective uptake of in is possible a of the in of the uptake of scavenger receptor class B type selective uptake of cholesteryl the of a the membrane and the the the in the the cell of the a on the selective uptake the of in its the cell major of the and by phospholipid is a major of the and of by scavenger receptor the of the of is by in the of SM the of the possible of on the selective uptake of We the SM the of by the of sphingomyelin in the of in the of and the of by the of and in the of of the and the of by SM is a of of sphingomyelin in of in investigated the effect of SM and its on the SR-BI-mediated selective uptake of the uptake by different cell is by SM by membrane SM of the the selective effect different and and the as of in the of of of cholesteryl by the by of by of of in is by a of scavenger receptor the membrane and the in in and cells, the adrenocortical cells, by of in and the in and and by by a of the by and and selective uptake of cholesteryl of the selective uptake of of cholesteryl and in a of SM and where and the in of in a a of a of a of of the in of in and the by and on a and and and and the of and the of SM of the the of of different of SM of as a of phospholipid the in the of SM as a of phospholipid the in in a of the and and in the by and in a of in of the and the by and and as by of by of the of and and uptake on a of and in the of cells, the three and in and and in and the and in of of the and cell and in a the of cell cell of by the the of in the cell of on the of and in the the of the selective uptake of uptake as of of cell uptake in and in by the cells, in the and as of sphingomyelin in the of in the of of and in the of of the and the of by of SM by the the of by by the of of the in membrane and as the on a a a as the and on as the and the by and the of on the and SM and a and of of SM and of SM by and the selective uptake of in CHO in the of SM of the uptake of by the in a uptake in CHO of the the cells, and by the effect of SM on the selective uptake of by CHO the phospholipid of by of SM the of of is in of the selective uptake by of the by the of is the the of sphingomyelin in the of in the of effect of SM on the uptake of is in the in uptake the of a by and the SM the effect of SM is the uptake in and the uptake in of SM in and SM by as in and of the is in the of phospholipid the SM the of uptake of in of the as of the uptake of the uptake of the in as of effect of SM investigated on the selective uptake by three different cell the SR-BI-transfected CHO in the adrenocortical cell SR-BI-mediated uptake of scavenger receptor class B type selective uptake of cholesteryl of the selective uptake of and the hepatocytes (HepG2), the in the in SM of the selective uptake of in cell the effect of SM is uptake of and by three different cell by of three cell of SM the effect of the of SM by the SM and the effect is in the of SM the of uptake in cell the of the selective uptake the of uptake is SM and in the of of SM SM of in the of and the by the of and by the selective uptake of by the three cell of SM of three of SM in uptake of is in and as in and and uptake of the and in the three different cell the selective uptake of by SM in the lipoproteins effect on selective in the of of in the of of and and as in the of and the and selective uptake by the three cell of SM of three of membrane is of the membrane and is the of the membrane rafts and where is a receptor selective is and and membrane B scavenger and of membrane in is the membrane SM role in the of the of and the selective uptake in the of membrane SM in of uptake the effect of the cell of the uptake of on the a of uptake the the by of cell of of CHO on selective uptake CHO the of and of the and of the cells, selective uptake in the of of of of and and the uptake of in the of and of three of is of and of the effect of the of in the of the selective uptake of in cell the in of the of a of uptake in the three cell in the of and a of SM in the the of of the SR-BI-mediated selective uptake of Although SM is the phospholipid in the its possible in SM sphingomyelin as a the SM the of by the of sphingomyelin in the of in the of and the of by the of and in the of of the and the of by the of by of sphingomyelin and on in of sphingomyelin and on the of by and the of of sphingomyelin in of in Although SM is the of the cell of its the of membrane on the of lipoproteins and different of of sphingomyelin and on in its possible role in the of lipoproteins and cell membranes the of the SR-BI-mediated uptake lipoproteins a by SM the selective uptake pathway is on the of SM on lipoproteins and cell membranes phospholipid is a major of the and of by scavenger receptor the of the SM its the of the the of SM in the the of the the cell the SM of the membrane the of the cell a phospholipid is a major of the and of by scavenger receptor the is and in and of the the and SM SM and of the of the in the selective uptake of is the of the and its and selective uptake of cholesteryl the role of in the selective Although of the in lipoproteins is in the of the of in the phospholipid in the and of the in the the of SM the of the cell is possible SM the of the of the of the of scavenger receptor of scavenger receptor class B type selective cholesteryl ester uptake by by of and the receptor scavenger receptor class B type of and on receptor role of membrane SM in the of selective uptake the is in the of the membrane B scavenger and of membrane in effect of of the cells, the three cell Although of CHO and the selective the effect on a by and of in membrane rafts of effect of on the selective uptake of by by of the in the the selective uptake the uptake three cell and the in the membrane different of and a membrane lipoproteins on the of CHO cells, on the of on the of the of in in a in the role of membrane SM in selective uptake the cell type and is of of the uptake the SM by uptake the the of in the the selective uptake of by CHO and cells, the effect on is is the of effect on on the rafts and and and in membranes of and of effect of its cell membranes the and its of membrane of CHO in the selective uptake the of uptake of the and in the SM and the SR-BI-mediated selective uptake of is the in of and of is scavenger receptor class B type I a membrane receptor the selective uptake of cholesteryl ester (CE) of the receptor on and is in the and and as a receptor the selective uptake of the uptake of is and is in the and sphingomyelin of membrane a receptor selective is and and membrane B scavenger and of membrane in the receptor in the a receptor selective is and and membrane the of is its and of in membrane rafts of its in selective uptake cholesteryl ester selective uptake in the cell of receptor in is the in of of and of and in the of the receptor on and of and and of and in scavenger receptor class B type I and of of the receptor on and its on of its of in the scavenger receptor by the selective uptake of is of by the selective of as a of in of scavenger receptor class B type of the membrane the selective uptake of in is possible a of the in of the uptake of scavenger receptor class B type selective uptake of cholesteryl the of a the membrane and the the the in the the cell of the a on the selective uptake the of in its the cell major of the and by phospholipid is a major of the and of by scavenger receptor the of the of is by in the of SM the of the possible of on the selective uptake of We the SM the of by the of sphingomyelin in the of in the of and the of by the of and in the of of the and the of by SM is a of of sphingomyelin in of in investigated the effect of SM and its on the SR-BI-mediated selective uptake of the uptake by different cell is by SM by membrane SM of the the selective effect different and and the as of in the of of of cholesteryl by the by of by of of in is by a of scavenger receptor the membrane and the in in and cells, the adrenocortical cells, by of in and the in and and by by a of the by and and selective uptake of cholesteryl of the selective uptake of of cholesteryl and in a of SM and where and the in of in a a of a of a of of the in of in and the by and on a and and and and the of and the of SM of the the of of different of SM of as a of phospholipid the in the of SM as a of phospholipid the in in a of the and and in the by and in a of in of the and the by and and as by of by of the of and and uptake on a of and in the of cells, the three and in and and in and the and in of of the and cell and in a the of cell cell of by the the of in the cell of on the of and in the the of the selective uptake of uptake as of of cell uptake in and in by the cells, in the and as of sphingomyelin in the of in the of of and in the of of the and the of by of SM by the the of by by the of of the in membrane and as the on a a a as the and on as the and the by and the of on the and SM and a and of and and the as of in the of of of cholesteryl by the by of by and and the as of in the of of of cholesteryl by the by of by of of in is by a of scavenger receptor the membrane and the in in and cells, the adrenocortical cells, by of in and the in and CHO of of in is by a of scavenger receptor the membrane and the in in and cells, the adrenocortical cells, by of in and the in and and by by a of the by and and selective uptake of cholesteryl of the selective uptake of of cholesteryl and in a of SM and where and the in of in a a of a of a of of the in of in and the by and on a and and and and the of and the of SM of the the of of different of SM of as a of phospholipid the in the of SM as a of phospholipid the in in a and by by a of the by and and selective uptake of cholesteryl of the selective uptake of of cholesteryl and in a of SM and where and the in of in a a of a of a of of the in of in and the by and on a and and and and the of and the of SM of the the of the of of the and and in the by and in a of in of the and the by and and as by of by of the of and and the and and in the by and in a of in of the and the by and and as by of by of the of and and uptake on a of and in the of cells, the three and in and and in and the and in of of the and cell and in a the of cell cell of by the the of in the cell of on the of and in the the of the selective uptake of uptake as of of cell uptake in and in by the cells, in the on a of and in the of cells, the three and in and and in and the and in of of the and cell and in a the of cell cell of by the the of in the cell of on the of and in the the of the selective uptake of uptake as of of cell uptake in and in by the cells, in the and as of sphingomyelin in the of in the of of and in the of of the and the of by of SM by the the of by and as of sphingomyelin in the of in the of of and in the of of the and the of by of SM by the the of by by the of of the in membrane and as the on a a a as the and on as the and the by and the of on the and SM and a and of by the of of the in membrane and as the on a a a as the and on as the and the by and the of on the and SM and a and of of SM and of SM by and the selective uptake of in CHO in the of SM of the uptake of by the in a uptake in CHO of the the cells, and by the effect of SM on the selective uptake of by CHO the phospholipid of by of SM the of of is in of the selective uptake by of the by the of is the the of sphingomyelin in the of in the of effect of SM on the uptake of is in the in uptake the of a by and the SM the effect of SM is the uptake in and the uptake in effect of SM investigated on the selective uptake by three different cell the SR-BI-transfected CHO in the adrenocortical cell SR-BI-mediated uptake of scavenger receptor class B type selective uptake of cholesteryl of the selective uptake of and the hepatocytes (HepG2), the in the in SM of the selective uptake of in cell the effect of SM is uptake of and by three different cell by of three cell of SM the effect of the of SM by the SM and the effect is in the of SM the of uptake in cell the of the selective uptake the of uptake is SM and in the of of SM SM of in the of and the by the of and by the selective uptake of by the three cell of SM of three of SM in uptake of is in and as in and and uptake of the and in the three different cell the selective uptake of by SM in the lipoproteins effect on selective in the of of in the of of and and as in the of and the and selective uptake by the three cell of SM of three of membrane is of the membrane and is the of the membrane rafts and where is a receptor selective is and and membrane B scavenger and of membrane in is the membrane SM role in the of the of and the selective uptake in the of membrane SM in of uptake the effect of the cell of the uptake of on the a of uptake the the by of cell of of CHO on selective uptake CHO the of and of the and of the cells, selective uptake in the of of of of and and the uptake of in the of and of three of is of and of the effect of the of in the of the selective uptake of in cell the in of the of a of uptake in the three cell in the of and of SM and of SM by and the selective uptake of in CHO in the of SM of the uptake of by the in a uptake in CHO of the the cells, and by the effect of SM on the selective uptake of by CHO the phospholipid of by of SM the of of is in of the selective uptake by of the by the of is the the of sphingomyelin in the of in the of effect of SM on the uptake of is in the in uptake the of a by and the SM the effect of SM is the uptake in and the uptake in effect of SM investigated on the selective uptake by three different cell the SR-BI-transfected CHO in the adrenocortical cell SR-BI-mediated uptake of scavenger receptor class B type selective uptake of cholesteryl of the selective uptake of and the hepatocytes (HepG2), the in the in SM of the selective uptake of in cell the effect of SM is and of SM by and the selective uptake of in CHO in the of SM of the uptake of by the in a uptake in CHO of the the cells, and by the effect of SM on the selective uptake of by CHO the phospholipid of by of SM the of of is in of the selective uptake by of the by the of is the the of sphingomyelin in the of in the of effect of SM on the uptake of is in the in uptake the of a by and the SM the effect of SM is the uptake in and the uptake in effect of SM investigated on the selective uptake by three different cell the SR-BI-transfected CHO in the adrenocortical cell SR-BI-mediated uptake of scavenger receptor class B type selective uptake of cholesteryl of the selective uptake of and the hepatocytes (HepG2), the in the in SM of the selective uptake of in cell the effect of SM is of SM the effect of the of SM by the SM and the effect is in the of SM the of uptake in cell the of the selective uptake the of uptake is SM and in the of We the effect of the of SM by the SM and the effect is in the of SM the of uptake in cell the of the selective uptake the of uptake is SM and in the of of SM in uptake of is in and as in and and uptake of the and in the three different cell the selective uptake of by SM in the lipoproteins effect on selective in the of of in the uptake of is in and as in and and uptake of the and in the three different cell the selective uptake of by SM in the lipoproteins effect on selective in the of of in the of membrane is of the membrane and is the of the membrane rafts and where is a receptor selective is and and membrane B scavenger and of membrane in is the membrane SM role in the of the of and the selective uptake in the of membrane SM in of uptake the effect of the cell of the uptake of on the a of uptake the the by of cell of of and and the uptake of in the of and of three SM is of the membrane and is the of the membrane rafts and where is a receptor selective is and and membrane B scavenger and of membrane in is the membrane SM role in the of the of and the selective uptake in the of membrane SM in of uptake the effect of the cell of the uptake of on the a of uptake the the by of cell of is of and of the effect of the of in the of the selective uptake of in cell the in is of and of the effect of the of in the of the selective uptake of in cell the in a of SM in the the of of the SR-BI-mediated selective uptake of Although SM is the phospholipid in the its possible in SM sphingomyelin as a the SM the of by the of sphingomyelin in the of in the of and the of by the of and in the of of the and the of by the of by of sphingomyelin and on in of sphingomyelin and on the of by and the of of sphingomyelin in of in Although SM is the of the cell of its the of membrane on the of lipoproteins and different of of sphingomyelin and on in its possible role in the of lipoproteins and cell membranes the of the SR-BI-mediated uptake lipoproteins a by SM the selective uptake pathway is on the of SM on lipoproteins and cell membranes phospholipid is a major of the and of by scavenger receptor the of the SM its the of the the of SM in the the of the the cell the SM of the membrane the of the cell a phospholipid is a major of the and of by scavenger receptor the is and in and of the the and SM SM and of the of the in the selective uptake of is the of the and its and selective uptake of cholesteryl the role of in the selective Although of the in lipoproteins is in the of the of in the phospholipid in the and of the in the the of SM the of the cell is possible SM the of the of the of the of scavenger receptor of scavenger receptor class B type selective cholesteryl ester uptake by by of and the receptor scavenger receptor class B type of and on receptor role of membrane SM in the of selective uptake the is in the of the membrane B scavenger and of membrane in effect of of the cells, the three cell Although of CHO and the selective the effect on a by and of in membrane rafts of effect of on the selective uptake of by by of the in the the selective uptake the uptake three cell and the in the membrane different of and a membrane lipoproteins on the of CHO cells, on the of on the of the of in in a in the role of membrane SM in selective uptake the cell type and is of of the uptake the SM by uptake the the of in the the selective uptake of by CHO and cells, the effect on is is the of effect on on the rafts and and and in membranes of and of effect of its cell membranes the and its of membrane of CHO in the selective uptake the of uptake of the and in the SM and the SR-BI-mediated selective uptake of a of SM in the the of of the SR-BI-mediated selective uptake of Although SM is the phospholipid in the its possible in SM sphingomyelin as a the SM the of by the of sphingomyelin in the of in the of and the of by the of and in the of of the and the of by the of by of sphingomyelin and on in of sphingomyelin and on the of by and the of of sphingomyelin in of in Although SM is the of the cell of its the of membrane on the of lipoproteins and different of of sphingomyelin and on in its possible role in the of lipoproteins and cell membranes the of the SR-BI-mediated uptake lipoproteins a by SM the selective uptake pathway is on the of SM on lipoproteins and cell membranes phospholipid is a major of the and of by scavenger receptor the of the SM its the of the the of SM in the the of the the cell the SM of the membrane the of the cell a phospholipid is a major of the and of by scavenger receptor the is and in and of the the and SM SM and of the of the in the selective uptake of is the of the and its and selective uptake of cholesteryl the role of in the selective Although of the in lipoproteins is in the of the of in the phospholipid in the and of the in the the of SM the of the cell is possible SM the of the of the of the of scavenger receptor of scavenger receptor class B type selective cholesteryl ester uptake by by of and the receptor scavenger receptor class B type of and on receptor role of membrane SM in the of selective uptake the is in the of the membrane B scavenger and of membrane in effect of of the cells, the three cell Although of CHO and the selective the effect on a by and of in membrane rafts of effect of on the selective uptake of by by of the in the the selective uptake the uptake three cell and the in the membrane different of and a membrane lipoproteins on the of CHO cells, on the of on the of the of in in a in the role of membrane SM in selective uptake the cell type and is of of the uptake the SM by uptake the the of in the the selective uptake of by CHO and cells, the effect on is is the of effect on on the rafts and and and in membranes of and of effect of its cell membranes the and its of membrane of CHO in the selective uptake the of uptake of the and in the SM and the SR-BI-mediated selective uptake of by of