title: Inclusion of calcium during isolation of high-density lipoprotein from plasma maintains antioxidant function.
abstract: We investigated how inclusion of calcium during isolation of high-density lipoprotein (HDL) affected its antioxidant function. Following isolation, HDL was dialyzed against 0.154 M NaCl without or with added calcium (1mM). HDL's paraoxonase 1 activity was unaffected by calcium treatment (87 ± 11% of normal vs. 89 ± 16% of normal, P=0.826). In contrast, whereas HDL dialyzed with calcium inhibited oxidation of low-density lipoprotein (LDL) by 87 ± 10%, HDL dialyzed without calcium inhibited oxidation by only 58 ± 19% (P=0.004). Thus, inclusion of calcium during isolation is important for maintaining HDL's antioxidant function.
authors.affiliation: Department of Biochemistry, Midwestern University, Downers Grove, IL 60515, USA. Electronic address: slynch@midwestern.edu.
authors.forename: Sean M
authors.initials: SM
authors.lastname: Lynch
authors.affiliation: Department of Biochemistry, Midwestern University, Downers Grove, IL 60515, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Lorenz
authors.affiliation: Department of Biochemistry, Midwestern University, Downers Grove, IL 60515, USA.
authors.forename: Steven
authors.initials: S
authors.lastname: Klotz
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism; D002118:Calcium / Q000737:chemistry*; D005591:Chemical Fractionation / Q000379:methods*; D003956:Dialysis; D006801:Humans; D008075:Lipoproteins, HDL / Q000097:blood / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D000975:Antioxidants; D008075:Lipoproteins, HDL; D002118:Calcium
keywords: Antioxidant; Calcium; High-density lipoprotein; Low-density lipoprotein; Oxidation; Paraoxonase 1