| Autor: |
Xenia Moren, Sara Deakin, Ming-Lin Liu, Marja-Riitta Taskinen, Richard W. James |
| Jazyk: |
angličtina |
| Rok vydání: |
2008 |
| Předmět: |
|
| Zdroj: |
Journal of Lipid Research, Vol 49, Iss 6, Pp 1246-1253 (2008) |
| Druh dokumentu: |
article |
| ISSN: |
0022-2275 |
| DOI: |
10.1194/jlr.M700439-JLR200 |
| Popis: |
The subfraction distribution of HDL-associated peptides has implications for their functions and the impact of pathological modifications to lipoprotein metabolism on these functions. We have analyzed the subfraction distribution of paraoxonase-1 (PON1) and the consequences for enzyme activity and stability. HDL subfractions were defined by the presence (LpA-I,A-II) or absence (LpA-I) of apolipoprotein A-II (apoA-II). PON1 was present in both subfractions, although increased concentrations of HDL were associated with significantly increased PON1 in LpA-I. ApoA-II did not modify the capacity of native human HDL or reconstituted HDL to promote PON1 secretion from cells or to stabilize enzyme activity, nor did apoA-II decrease PON1 activity when added to rabbit serum normally devoid of the apolipoprotein. LpA-I,A-II particles isolated from human serum or reconstituted HDL (LpA-I,A-II) showed a significantly greater capacity than HDL(LpA-I) to stabilize secreted PON1 and purified recombinant PON1 added to such particles. PON1 associated with apoA-II-containing particles showed greater resistance to inactivation arising from oxidation. ApoA-I, apoA-II, and LpA-I,A-II, but not LpA-I, were independent determinants of serum PON1 concentration and activity in multivariate analyses. PON1 is at least equally distributed between LpA-I and LpA-II,A-II HDL particles. This dichotomous distribution has implications for PON1 activity and stability that may impact on the physiological role of the enzyme. |
| Databáze: |
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| Externí odkaz: |
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