A point mutant of apolipoprotein A-I, V156K, exhibited potent anti-oxidant and anti-atherosclerotic activity in hypercholesterolemic C57BL/6 mice.
- Author:
Kyung Hyun CHO
1
;
Sun Hyun PARK
;
Jong Min HAN
;
Hyoung Chin KIM
;
Young Jin CHUNG
;
Inho CHOI
;
Jae Ryong KIM
Author Information
1. School of Biotechnology and Aging-associated Vascular Disease Research Center Yeungnam University Gyeongsan 712-749, Korea. chok@yu.ac.kr
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
antioxidants;
apolipoprotein A-I;
atherosclerosis;
lipoproteins, HDL;
mutant proteins
- MeSH:
Amino Acids/*genetics;
Animals;
Antioxidants/*metabolism;
Apolipoprotein A-I/*genetics;
Atherosclerosis/*pathology;
Biological Transport/drug effects;
Cell Line, Tumor;
Cholesterol/metabolism;
Copper/pharmacology;
Humans;
Hypercholesterolemia/chemically induced/*pathology;
Lipoproteins, HDL/blood;
Lipoproteins, LDL/blood;
Male;
Mice;
Mice, Inbred C57BL;
Oxidation-Reduction/drug effects;
Point Mutation/*genetics;
Recombinant Proteins/blood
- From:Experimental & Molecular Medicine
2007;39(2):160-169
- CountryRepublic of Korea
- Language:English
-
Abstract:
In our previous study, two point mutants of apolipoprotein A-I, designated V156K and A158E, revealed peculiar characteristics in their lipid-free and lipid-bound states. In order to determine the putative therapeutic potential of these mutants, several in vitro and in vivo evaluations were conducted. In the lipid-free state, V156K showed more profound antioxidant activity against LDL oxidation than did the wildtype (WT) or A158E variants in an in vitro assay. In the lipid-bound state, V156K-rHDL showed an enhanced cholesterol delivery activity to HepG2 cells in a time-dependent manner, as compared to WT-rHDL, A158E-rHDL, and R173C-rHDL. We assessed the physiological activities of the mutants in circulation, using hypercholesterolemic mice (C57BL6/J). Palmitoyloleoyl phosphatidylcholine (POPC)-rHDL preparations containing each of the apoA-I variants were injected into the mice at a dosage of 30 mg of apoA-I/kg of body weight. Forty eight hours after injection, the sera of the V156K-rHDL injected group showed the most potent antioxidant abilities in the ferric acid removal assay. The V156K-rHDL- or R173C-rHDL-injected mice showed no atherosclerotic lesions and manifested striking increases in their serum apo-E levels, as compared to the mice injected with WT-rHDL or A158E-rHDL. In conclusion, V156K-rHDL exhibited the most pronounced antioxidant activity and anti-atherosclerotic activity, both in vitro and in vivo. These results support the notion that HDL-therapy may prove beneficial due to its capacity to induce accelerated cholesterol excretion, as well as its enhanced antioxidant and anti-inflammatory effects and lesion regression effect.
