Copper induces the expression of cholesterogenic genes in human macrophages.
Accumulation of lipids and cholesterol by macrophages and subsequent transformation into foam cells are key features in development of atherosclerosis. Serum copper concentrations have been shown to be associated with cardiovascular disease. However, the mechanism behind the proatherogenic effect of copper is not clear. We used DNA microarrays to define the changes in gene expression profile in response to copper exposure of human macrophages. Expression monitoring by DNA microarray revealed 91 genes that were regulated. Copper increased the expression of seven cholesterogenic genes (3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) synthase, IPP isomerase, squalene synthase, squalene epoxidase, methyl sterol oxidase, H105e3 mRNA and sterol-C5-desaturase) and low-density lipoprotein receptor (LDL-R), and decreased the expression of CD36 and lipid binding proteins. The expression of LDL-R and HMG CoA reductase was also investigated using real time PCR. The expression of both of these genes was increased after copper treatment of macrophages (P<0.01 and P<0.01, respectively). We conclude that copper activates cholesterogenic genes in macrophages, which may provide a mechanism for the association between copper and atherosclerosis. The effect of copper on cholesterogenic genes may also have implications for liver steatosis in early stages of Wilson's disease.
Svensson
Per Arne
PA
Department of Internal Medicine, Research Centre for Endocrinology and Metabolism (RCEM), Vita Stråket 12, Sahlgrenska Academy, Göteborg University, S-41345 Gothenburg, Sweden. per-arne.svensson@medic.gu.se
Englund
Mikael C O
MC
Markström
Emilia
E
Ohlsson
Bertil G
BG
Jernås
Margareta
M
Billig
Håkan
H
Torgerson
Jarl S
JS
Wiklund
Olov
O
Carlsson
Lena M S
LM
Carlsson
Björn
B
D002784:Cholesterol / Q000235:genetics*; D019327:Copper Sulfate / Q000494:pharmacology*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D006903:Hydroxymethylglutaryl CoA Reductases / Q000235:genetics / Q000378:metabolism; D066298:In Vitro Techniques; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D011973:Receptors, LDL / Q000235:genetics / Q000378:metabolism
D011973:Receptors, LDL; D002784:Cholesterol; D006903:Hydroxymethylglutaryl CoA Reductases; D019327:Copper Sulfate