Abstract:

Objective To study the protective effect of miR⁃29a on LPS induced rat renal tubular epithelialcell injury by targeting signal transduction and activator of transcription 3（STAT3）. Methods Rat renal tubularepithelial cell line NRK⁃52E was cultured. LPS stimulation was used to establish sepsis cell model and induce cellinjury，then transfected with miR⁃nc，miR⁃29a，pcDNA3.1 plasmid，pcDNA3.1⁃STAT3 plasmid or treated withSTAT3 inhibitor AG490. Then cell viability A490，the expression of STAT3，p⁃STAT3 and Bcl⁃2，TNF⁃α andIL⁃β contents were compared，and miR⁃29a targeting STAT3 was confirmed by double luciferase reporter gene.Result The expression levels of miR⁃29a，Bcl⁃2，the level of A490 of LPS group were lower than those of the con⁃trol group，while the expression of STAT3，p⁃STAT3，the contents of TNF⁃α and IL⁃β were higher than those incontrol group；the expression levels of miR⁃29a，Bcl⁃2，the level of A490 of LPS+miR⁃29a group were higher thanthose of the LPS group，while the expression of STAT3，p⁃STAT3，the contents of TNF⁃α and IL⁃β were lowerthan those in LPS group；the expression levels of Bcl⁃2，the level of A490 of pcDNA3.1⁃STAT3+miR⁃29a were low⁃er than pcDNA3.1+miR⁃29a group，while the expression of STAT3，p⁃STAT3，the contents of TNF⁃α and IL⁃βwere higher than those in LPS group；the fluorescence activity of STAT3 double luciferase reporter gene of miR⁃29agroup was lower than that of miR⁃nc group. Conclusion STAT3 pathway activation is related to LPS inducedinflammatory response and apoptosis of renal tubular epithelial cells，miR⁃29a can reduce LPS induced inflammatoryresponse and apoptosis by targeting STAT3.

Key words: sepsis, lipopolysaccharide, miR?29a, signal transduction and activator of transcription 3, renal tubular epithelial cells, apoptosis, inflammatory response