title: Interleukin-10 down-regulates oxLDL induced expression of scavenger receptor A and Bak-1 in macrophages derived from THP-1 cells.
abstract: Here, we investigated the therapeutic potential of IL-10 by testing its effects on oxLDL-induced lipoprotein uptake and apoptosis by flow cytometry in THP-1-derived macrophages. The mRNA and protein expressions of lipid scavenger receptors (SR-A, CD36) and apoptosis-related proteins (Bcl-2, Bak-1) were also detected. Co-incubation of oxLDL with IL-10 reduced DiI-oxLDL uptake by 16.1±3.8%, 35.2±3.8% and 28.9±1.8% at 6, 12 and 24h of treatment, respectively. Furthermore, treatment with oxLDL for 24h enhanced the SR-A mRNA and protein expressions by 89.3±17.1% and 70.1±17.6%, respectively. IL-10 abrogated the oxLDL-induced SR-A mRNA expression by 50.2±3.9% and its protein by 45.6±1.9%. Meanwhile IL-10 had no effect on the oxLDL-induced increase of CD36 expression. IL-10 inhibited the oxLDL-induced cell apoptosis in a time-dependent manner by 17.3±3.3%, 36.4±2.8% and 31.0±4.3% at 6, 12 and 24h, respectively. OxLDL increased Bak-1 mRNA and protein expressions by 38.4±13.3% and 36.9±12.1%, respectively. However co-stimulation of oxLDL with IL-10 for 24h inhibited Bak-1 expression to 28.4±7.2% (mRNA) and 25.7±6.3% (protein). Meanwhile, IL-10 had no effect on the oxLDL-induced decrease of Bcl-2 expression. Our findings suggested that IL-10 reduced the oxLDL-induced lipoprotein uptake and apoptosis partly via down-regulating the oxLDL-induced expression of SR-A and Bak-1 in THP-1-derived macrophages.
authors.affiliation: Tongji University School of Medicine, Shanghai 200092, China. hyang@tongji.edu.cn
authors.forename: Hong
authors.initials: H
authors.lastname: Yang
authors.forename: Shichao
authors.initials: S
authors.lastname: Chen
authors.forename: Yongqing
authors.initials: Y
authors.lastname: Tang
authors.forename: Yalei
authors.initials: Y
authors.lastname: Dai
mesh_terms: D017209:Apoptosis; D018955:CD36 Antigens / Q000235:genetics; D002460:Cell Line; D015536:Down-Regulation; D006801:Humans; D016753:Interleukin-10 / Q000378:metabolism*; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008264:Macrophages / Q000166:cytology / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D051117:Scavenger Receptors, Class A / Q000235:genetics*; D050998:bcl-2 Homologous Antagonist-Killer Protein / Q000235:genetics*
chemical_list: C494772:BAK1 protein, human; D018955:CD36 Antigens; D008077:Lipoproteins, LDL; D012333:RNA, Messenger; D051117:Scavenger Receptors, Class A; D050998:bcl-2 Homologous Antagonist-Killer Protein; C099252:oxidized low density lipoprotein; D016753:Interleukin-10