Ghrelin down-regulates ACAT-1 in THP-1 derived foam cells via growth hormone secretagogue receptor-dependent pathway.
- Author:
Jing-Jing WAN
1
;
Bei CHENG
;
Yan-Fu WANG
;
Chun-Li MEI
;
Wei LIU
;
Li KE
;
Ping HE
Author Information
- Publication Type:Journal Article
- MeSH: Acetyl-CoA C-Acetyltransferase; metabolism; Acyl Coenzyme A; metabolism; Blotting, Western; Cell Line, Tumor; Cholesterol; metabolism; Down-Regulation; Foam Cells; metabolism; Ghrelin; physiology; Humans; RNA, Messenger; metabolism; Receptors, Ghrelin; physiology; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction; Spectrophotometry
- From: Chinese Journal of Cardiology 2009;37(11):1030-1034
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo investigate the effects of Ghrelin on the expression of acyl coenzyme A:cholesterol acyltransferases-1 (ACAT-1) in THP-1 derived foam cells.
METHODSThe human monocytic leukemia cell line (THP-1) was chosen in our study. The differentiation of THP-1 cells into macrophages was induced by phorbol 12-myristate 13-acetate. Macrophages were then incubated with oxidized LDL (ox-LDL) to generate foam cells. Ghrelin and [D-Lys3]-GHRP-6, the special antagonist of growth hormone secretagogue receptor (GHS-R), were treated during foam cells formation. The ACAT-1 protein and mRNA levels were detected by Western blot and RT-PCR. The effect of variance of cholesterol content was measured by zymochemistry via-fluorospectrophotometer.
RESULTSGhrelin reduced the content of cholesterol ester in foam cells obviously. ACAT-1 protein and mRNA levels were also decreased. The antagonist of GHS-R inhibited the effects of Ghrelin on ACAT-1 expression in dose-dependent manner. The ACAT-1 mRNA levels of the GHS-R specific antagonist groups (10(-5), 5 x 10(-5), 10(-4) mol/L) were 1.14 +/- 0.04, 1.58 +/- 0.03, 2.40 +/- 0.16, significantly higher than that of the Ghrelin group (0.89 +/- 0.05). And the protein expressions were 1.25 +/- 0.09, 1.77 +/- 0.11, 2.30 +/- 0.09, also higher than that of the Ghrelin group (0.86 +/- 0.08).
CONCLUSIONSGhrelin might interfere atherosclerosis by down-regulating the expression of ACAT-1 via GHS-R pathway.
