Toll-like receptor 4 is expressed and functional in late endothelial progenitor cells

作者：Yu, Min; Wang, Cantian; Zeng, Guoning; Zhou, Lihong; Chen, Tingting; Tan, Xuerui; Wang, Yanping^*

来源：Molecular Medicine Reports, 2017, 16(4): 5549-5554.

DOI：10.3892/mmr.2017.7291

• lipopolysaccharide
• late endothelial progenitor cells
• Toll-like receptor 4
• Silent information regulator 1
• lung injury
• functional activity

It has been previously demonstrated that lipopolysaccharides (LPS) inhibit the viability, migration, adhesion and in vitro angiogenesis of late endothelial progenitor cells (EPCs). However, the mechanisms underlying this LPS-induced impairment of late EPC functional activity are unknown. The aim of the present study was to investigate whether Toll-like receptor 4 (TLR4) is expressed and functional on late EPCs, using late EPCs of 3-5 passages. Cells were deprived of serum for 24 h prior to experiments and incubated with 10 mu g/ml LPS for 24 h with or without pretreatment with 2 mu g/ml TLR4 signaling inhibitor CLI-095 for 30 min. The viability, migration, adhesion and in vitro angiogenesis, as well as the expression of silent information regulator 1 (SIRT1), in late EPCs were evaluated. Treatment with 10 mu g/ml LPS decreased the viability, migration and adhesion abilities, and in vitro angiogenesis of late EPCs. Pretreatment with the TLR4 signaling inhibitor reversed this LPS-induced dysfunction of late EPCs. LPS downregulated the expression of SIRT1 protein, however, blocking TLR4 attenuated the effect of LPS on SIRT1 expression. Therefore, the results of the present study indicate that LPS impaired the functional activity of late EPCs via TLR4, which may be associated with decreased SIRT1 expression.

• 出版日期2017-10
• 单位汕头大学