l-Cystathionine Inhibits the Mitochondria-Mediated Macrophage Apoptosis Induced by Oxidized Low Density Lipoprotein

• Main Authors: Mingzhu Zhu, Junbao Du, Siyao Chen, Angie Dong Liu, Lukas Holmberg, Yonghong Chen, Chunyu Zhang, Chaoshu Tang, Hongfang Jin
• Format: Article
• Language: English
• Published: MDPI AG 2014-12-01
• Series: International Journal of Molecular Sciences
• Subjects: l-cystathionine; ox-LDL; macrophage; mitochondrial; oxidative stress; apoptosis; caspase-9; caspase-3
• Online Access: http://www.mdpi.com/1422-0067/15/12/23059

This study was designed to investigate the regulatory role of l-cystathionine in human macrophage apoptosis induced by oxidized low density lipoprotein (ox-LDL) and its possible mechanisms. THP-1 cells were induced with phorbol 12-myristate 13-acetate (PMA) and differentiated into macrophages. Macrophages were incubated with ox-LDL after pretreatment with l-cystathionine. Superoxide anion, apoptosis, mitochondrial membrane potential, and mitochondrial permeability transition pore (MPTP) opening were examined. Caspase-9 activities and expression of cleaved caspase-3 were measured. The results showed that compared with control group, ox-LDL treatment significantly promoted superoxide anion generation, release of cytochrome c (cytc) from mitochondrion into cytoplasm, caspase-9 activities, cleavage of caspase-3, and cell apoptosis, in addition to reduced mitochondrial membrane potential as well as increased MPTP opening. However, 0.3 and 1.0 mmol/L l-cystathionine significantly reduced superoxide anion generation, increased mitochondrial membrane potential, and markedly decreased MPTP opening in ox-LDL + l-cystathionine macrophages. Moreover, compared to ox-LDL treated-cells, release of cytc from mitochondrion into cytoplasm, caspase-9 activities, cleavage of caspase-3, and apoptosis levels in l-cystathionine pretreated cells were profoundly attenuated. Taken together, our results suggested that l-cystathionine could antagonize mitochondria-mediated human macrophage apoptosis induced by ox-LDL via inhibition of cytc release and caspase activation.