Apolipoprotein M affecting lipid metabolism or just catching a ride with lipoproteins in the circulation?

TY - JOUR

T1 - Apolipoprotein M affecting lipid metabolism or just catching a ride with lipoproteins in the circulation?

AU - Dahlbäck, B

AU - Nielsen, Lars Bo

N1 - Keywords: Animals; Apolipoproteins; Atherosclerosis; Cholesterol; Humans; Kidney Tubules, Proximal; LDL-Receptor Related Protein 2; Lipid Metabolism; Lipoproteins; Major Histocompatibility Complex; Models, Molecular; Protein Sorting Signals; Protein Structure, Tertiary

PY - 2009

Y1 - 2009

N2 - Apolipoprotein M (apoM) is a novel apolipoprotein found mainly in high-density lipoproteins (HDL). Its function is yet to be defined. ApoM (25 kDa) has a typical lipocalin ss-barrel fold and a hydrophobic pocket. Retinoids bind apoM but with low affinity and may not be the natural ligands. ApoM retains its signal peptide, which serves as a hydrophobic anchor to the lipoproteins. This prevents apoM from being lost in the urine. Approximately 5% of HDL carries an apoM molecule. ApoM in plasma (1 microM) correlates strongly with both low-density lipoprotein (LDL) and HDL cholesterol, suggesting a link to cholesterol metabolism. However, in casecontrol studies, apoM levels in patients with coronary heart disease (CHD) and controls were similar, suggesting apoM levels not to affect the risk for CHD in humans. Experiments in transgenic mice suggested apoM to have antiatherogenic properties; possible mechanisms include increased formation of pre-ss HDL, enhanced cholesterol mobilization from foam cells, and increased antioxidant properties.

AB - Apolipoprotein M (apoM) is a novel apolipoprotein found mainly in high-density lipoproteins (HDL). Its function is yet to be defined. ApoM (25 kDa) has a typical lipocalin ss-barrel fold and a hydrophobic pocket. Retinoids bind apoM but with low affinity and may not be the natural ligands. ApoM retains its signal peptide, which serves as a hydrophobic anchor to the lipoproteins. This prevents apoM from being lost in the urine. Approximately 5% of HDL carries an apoM molecule. ApoM in plasma (1 microM) correlates strongly with both low-density lipoprotein (LDL) and HDL cholesterol, suggesting a link to cholesterol metabolism. However, in casecontrol studies, apoM levels in patients with coronary heart disease (CHD) and controls were similar, suggesting apoM levels not to affect the risk for CHD in humans. Experiments in transgenic mice suggested apoM to have antiatherogenic properties; possible mechanisms include increased formation of pre-ss HDL, enhanced cholesterol mobilization from foam cells, and increased antioxidant properties.

U2 - 10.1007/s00018-009-8764-8

DO - 10.1007/s00018-009-8764-8

M3 - Journal article

C2 - 19153651

SN - 1023-294X

VL - 66

SP - 559

EP - 564

JO - EXS

JF - EXS

IS - 4

ER -