Study on Molecular Mechanism of CircRNA ANKRD36 Regulating Apoptosis and Oxidative Stress of Vascular Endothelial cells in Sepsis by Targeting miR-127-5p

In order to explore the effect and possible mechanism of CircRNA ANKRD36 on the apoptosis and oxidative stress of vascular endothelial cells in sepsis, CircRNA ANKRD36 small interfering RNA, miR-127-5p mimic or CircRNA ANKRD36 small interfering RNA and miR-127-5p inhibitor were transfected into human umbilical

vein endothelial cells, and then 1.0 μg/mL LPS was used to intervene the transfected cells for 24 h. RT-qPCR method was used to detect the expression of CircRNA ANKRD36 and miR-127-5p in the cells. Flow cytometry was used to detect cell apoptosis. Western blot was used to detect the protein expression of Cleaved-Caspase-3 in cells. DCFH-DA probe method was used to detect the level of ROS. Thiobarbituric acid method was used to detect the content of MDA in cells. Xanthine oxidase method was used to detect the activity of SOD in cells. In addition, the dual luciferase reporter gene experiment verified the regulatory relationship between CircRNA ANKRD36 and miR-127-5p. The results showed that LPS promoted the expression of CircRNA ANKRD36 in vascular endothelial cells (P<0.05), but it inhibited the expression of miR-127-5p (P<0.05). Down-regulating CircRNA ANKRD36 or up-regulating miR-127-5p reduced LPS-induced vascular endothelial cells apoptosis, the expression of Cleaved-Caspase-3 protein expression, the level of ROS and the content of MDA in cells (P<0.05), but increased the activity of SOD in cells (P<0.05). CircRNA ANKRD36 could target to regulate the expression of miR-127-5p. Down-regulating miR-127-5p reversed the effect of down-regulating CircRNA ANKRD36 on LPS-induced vascular endothelial cell apoptosis and oxidative stress. This suggested that down-regulating CircRNA ANKRD36 might inhibit LPS-induced vascular endothelial cell apoptosis and oxidative stress by up-regulating the expression of miR-127-5p. CircRNA ANKRD36/miR-127-5p axis may provide new molecular targets for the treatment of sepsis.

CSTR: 32200.14.cjcb.2021.09.0004