Reduced beta2-glycoprotein I protects macrophages from ox-LDL-induced foam cell formation and cell apoptosis

Lipids in Health and Disease

Pei Yu¹  De-Min Yu¹  Ze-Jun Ma¹  Lin Lv¹  Rui Chen¹  Chun-Jun Li¹  Sai-Jun Zhou¹  Zhen-Xing Meng¹  Wei-Lin Wang¹ 

[1]2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics, the Key Laboratory of Hormones and Development (Ministry of Health), Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, 300070, Tianjin, China

关键词: Apoptosis;    Foam cell;    Ox-LDL;    Beta2-glycoprotein I;    Reduced beta2-glycoprotein I;   

Others  :  829172
DOI  :  10.1186/1476-511X-12-174

 received in 2013-08-10, accepted in 2013-11-11,  发布年份 2013

【 摘 要 】

Background

Reduced beta2-glycoprotein I (beta2-GPI) is a free thiol-containing form of beta2-GPI that displays a powerful effect in protecting endothelial cells from oxidative stress-induced cell death. The present study aims to investigate the effect of beta2-GPI or reduced beta2-GPI on ox-LDL-induced foam cell formation and on cell apoptosis and to determine the possible mechanisms.

Methods

The RAW264.7 macrophage cell line was selected as the experimental material. Oil red O staining and cholesterol measurement were used to detect cholesterol accumulation qualitatively and quantitatively, respectively. Flow cytometry was used to detect cell apoptosis. Real-time quantitative PCR was used to detect the mRNA expression of the main proteins that are associated with the transport of cholesterol, such as CD36, SRB1, ABCA1 and ABCG1. Western blot analysis was used to detect the protein expression of certain apoptosis-related proteins, such as caspase-9, caspase-3, p38 MAPK/p-p38 MAPK and JNK/p-JNK.

Results

Beta2-GPI or reduced beta2-GPI decreased ox-LDL-induced cholesterol accumulation (96.45 ± 8.51 μg/mg protein vs. 114.35 ± 10.38 μg/mg protein, p < 0.05;74.44 ± 5.27 μg/mg protein vs. 114.35 ± 10.38 μg/mg protein, p < 0.01) and cell apoptosis (30.00 ± 5.10% vs. 38.70 ± 7.76%, p < 0.05; 20.66 ± 2.50% vs. 38.70 ± 7.76%, p < 0.01), and there are significant differences between beta2-GPI and reduced beta2-GPI (p < 0.05). Reduced beta2-GPI decreased the ox-LDL-induced expression of CD36 mRNA and ABCA1 mRNA (p < 0.05), as well as CD36, cleaved caspase-9, cleaved caspase-3, p-p38 MAPK and p-JNK proteins (p < 0.05 or p < 0.01). Beta2-GPI did not significantly decrease the expression of ABCA1 mRNA and the p-p38 MAPK protein.

Conclusions

Both beta2-GPI and reduced beta2-GPI inhibit ox-LDL-induced foam cell formation and cell apoptosis, and the latter exhibits a stronger inhibition effect. Both of these glycoproteins reduce the lipid intake of macrophages by downregulating CD36 as well as protein expression. Reduced beta2-GPI inhibits cell apoptosis by reducing the ox-LDL-induced phosphorylation of p38 MAPK and JNK, and the amount of cleaved caspase-3 and caspase-9. Beta2-GPI does not inhibit the ox-LDL-induced phosphorylation of p38 MAPK.

【 授权许可】

   
2013 Wang et al.; licensee BioMed Central Ltd.

【 图 表 】

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