TY - JOUR
T1 - Scavenger receptor class B type i protein as an independent predictor of high-density lipoprotein cholesterol levels in subjects with hyperalphalipoproteinemia
AU - West, Michael
AU - Greason, Erin
AU - Kolmakova, Antonina
AU - Jahangiri, Anisa
AU - Asztalos, Bela
AU - Pollin, Toni I.
AU - Rodriguez, Annabelle
N1 - Funding Information:
This work was supported by a National Institutes of Health grant to A.R. (HL075646) and from The Johns Hopkins Bayview Medical Center General Clinical Research Center (M01-RR-02179). None of the authors report a financial conflict of interest.
PY - 2009/4
Y1 - 2009/4
N2 - Context: In mice, scavenger receptor class B, type I (SR-BI) receptor protein deficiency is associated with elevated high-density lipoprotein (HDL)-cholesterol (HDL-C) levels. Objective: Our objective was to determine the relationship between SR-BI protein and HDL-C levels in humans. Design: This was a prospective study of adults with hyperalphalipoproteinemia. Fasting blood was obtained for lipid and lipoprotein measurement, genomic DNA, and monocyte-derived macrophages. SR-BI protein levels were measured by Western blots, and SR-BI activity was measured by cholesteryl ester (CE) uptake of each donor's radiolabeled HDL with their monocyte-derived macrophages, or by degradation and specific cell association of dual-labeled HDL in vitro. Setting: The study was performed in a tertiary university teaching hospital. Results: The mean age was 57.2 ± 10.9 yr (n = 65). SR-BI protein levels were inversely associated with HDL-C levels (P < 0.002), HDL particle size (P < 0.05), and positively associated with CE uptake (P < 0.004); there was no association with plasma apolipoprotein levels. SR-BI protein levels (P = 0.01) were independent predictors of HDL-C levels. Subjects who were carriers of the A allele for the rs4238001 (glycine to serine at position 2) polymorphism [single nucleotide polymorphism (SNP)] had lower SR-BI protein levels (P = 0.01), whereas carriers of the C allele for the rs2278986 SNP also had lower SR-BI protein levels (P = 0.02). Body mass index (P = 0.05), rs4238001 (P = 0.01), and rs2278986 (P = 0.01) SNPs were independent predictors of SR-BI protein levels. In vitro studies of murine macrophages stably expressing the glycine to serine at position 2 SNP showed less degradation (P < 0.0004) and specific cell association (P < 0.0004) of [125I, 3H]-CE-labeled HDL. Conclusions: SR-BI protein has an independent effect on HDL-C levels in women with hyperalphalipoproteinemia. Two SNPs were significantly associated with lower SR-BI protein levels.
AB - Context: In mice, scavenger receptor class B, type I (SR-BI) receptor protein deficiency is associated with elevated high-density lipoprotein (HDL)-cholesterol (HDL-C) levels. Objective: Our objective was to determine the relationship between SR-BI protein and HDL-C levels in humans. Design: This was a prospective study of adults with hyperalphalipoproteinemia. Fasting blood was obtained for lipid and lipoprotein measurement, genomic DNA, and monocyte-derived macrophages. SR-BI protein levels were measured by Western blots, and SR-BI activity was measured by cholesteryl ester (CE) uptake of each donor's radiolabeled HDL with their monocyte-derived macrophages, or by degradation and specific cell association of dual-labeled HDL in vitro. Setting: The study was performed in a tertiary university teaching hospital. Results: The mean age was 57.2 ± 10.9 yr (n = 65). SR-BI protein levels were inversely associated with HDL-C levels (P < 0.002), HDL particle size (P < 0.05), and positively associated with CE uptake (P < 0.004); there was no association with plasma apolipoprotein levels. SR-BI protein levels (P = 0.01) were independent predictors of HDL-C levels. Subjects who were carriers of the A allele for the rs4238001 (glycine to serine at position 2) polymorphism [single nucleotide polymorphism (SNP)] had lower SR-BI protein levels (P = 0.01), whereas carriers of the C allele for the rs2278986 SNP also had lower SR-BI protein levels (P = 0.02). Body mass index (P = 0.05), rs4238001 (P = 0.01), and rs2278986 (P = 0.01) SNPs were independent predictors of SR-BI protein levels. In vitro studies of murine macrophages stably expressing the glycine to serine at position 2 SNP showed less degradation (P < 0.0004) and specific cell association (P < 0.0004) of [125I, 3H]-CE-labeled HDL. Conclusions: SR-BI protein has an independent effect on HDL-C levels in women with hyperalphalipoproteinemia. Two SNPs were significantly associated with lower SR-BI protein levels.
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U2 - 10.1210/jc.2008-1223
DO - 10.1210/jc.2008-1223
M3 - Article
C2 - 19158204
AN - SCOPUS:65249113906
SN - 0021-972X
VL - 94
SP - 1451
EP - 1457
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
IS - 4
ER -