Leukotriene D4 induces cellular senescence in osteoblasts

• Published in: International immunopharmacology 2018-05, Vol.58, p.154-159
• Main Authors: Wei, Jinsong, Chen, Siyuan, Guo, Weixiong, Feng, Bailin, Yang, Shukai, Huang, Chengshuo, Chu, Jiaqi
• Format: Article
• Language: English
• Subjects: Acetates - pharmacology; Aging; Animals; Arachidonic acid; beta-Galactosidase - metabolism; Biocompatibility; Bone density; Cell Line; Cellular Senescence; Cyclin-dependent kinase inhibitor p21; Cyclin-Dependent Kinase Inhibitor p21 - metabolism; Cyclopropanes; Galactosidase; Humans; Inflammation; Leukotriene D4; Leukotriene D4 - metabolism; Medical treatment; Mice; Montelukast; mRNA; Osteoblasts; Osteoblasts - physiology; Osteoporosis; Osteoporosis - immunology; p53 Protein; Pathogenesis; Plasminogen Activator Inhibitor 1 - metabolism; Plasminogen activator inhibitors; Proteins; Quinolines - pharmacology; Receptors, Leukotriene - genetics; Receptors, Leukotriene - metabolism; RNA, Small Interfering - genetics; Senescence; siRNA; SIRT1; SIRT1 protein; Sirtuin 1 - metabolism; Sulfides; Transfection; Tumor Suppressor Protein p53 - metabolism; β-Galactosidase
• ISSN: 1567-5769; 1878-1705
• DOI: 10.1016/j.intimp.2017.12.027

Aging is associated with the development of osteoporosis, in which cellular senescence in osteoblasts plays a key role. Leukotriene D4 (LTD4), an important cysteinyl leukotriene (cysLT), is a powerful pro-inflammatory mediator formed from arachidonic acid. However, little information regarding the effects of LTD4 on the pathogenesis of osteoporosis has been reported before. In the present study, we defined the physiological roles of LTD4 in cellular senescence in osteoblasts. Our results indicate that LTD4 treatment decreased the expression of SIRT1 in a dose-dependent manner in MC3T3-E1 osteoblastic cells. Additionally, LTD4 significantly increased the expression of p53, p21 and plasminogen activator inhibitor-1 (PAI-1). LTD4 was also found to elevate the activity of β-galactosidase (SA-β-Gal) but to prevent BrdU incorporation. Our results indicate that cysteinyl leukotriene receptor 1 (cysLT1R) could be detected in MC3T3-E1 osteoblastic cells at both the mRNA and protein levels. However, cysLT2R was not expressed in these cells. Interestingly, we found that knockdown of cysLT1R or use of the selective cysLT1R antagonist montelukast abolished the LTD4-induced reduction in SIRT1 and increase in p53, p21, and PAI-1. Notably, knockdown of cysLT1R by transfection with cysLT1R siRNA or treatment with montelukast attenuated the LTD4-induced increase in SA-β-Gal activity. Our study shows for the first time that LTD4 has a significant impact on cellular senescence in osteoblasts. •LTD4 reduced SIRT1 but increased p53, p21, and PAI-1 in MC3T3-E1 osteoblastic cells.•LTD4 increased β-Galactosidase (SA-β-Gal) activity and reduced BrdU incorporation.•CysLT1R but not cysLT2R is expressed in MC3T3-E1 osteoblastic cells.•The effects of LTD4 on cellular senescence are dependent on cysLT1R.