The suppression of ox-LDL-induced inflammatory response and apoptosis of HUVEC by lncRNA XIAT knockdown via regulating miR-30c-5p/PTEN axis

OBJECTIVE: Exposure of oxidized low-density lipoprotein (ox-LDL) could cause dysfunction of HUVEC, thus leading to atherosclerosis development, which is a common inflammatory vascular disease. Long noncoding RNA X-inactive specific transcript (XIST) has been reported to be implicated in atherosclerosis. However, the mechanism by which this lncRNA participates in the progression of atherosclerosis is poorly defined. MATERIALS AND METHODS: HUVEC challenged by ox-LDL were used as a cellular model of atherosclerosis. Cell viability, apoptosis, LDH release, and inflammatory cytokines secretion were detected by MTT, flow cytometry, and ELISA assays. The expression levels of XIST, microRNA (miR)-30c-5p, and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) were measured by quantitative Real Time-Polymerase Chain Reaction and Western blot. The target interaction between XIST and miR-30c-5p or miR30c-5p and PTEN was validated by the Luciferase reporter assay and RNA immunoprecipitation. RESULTS: Treatment of ox-LDL induced cell apoptosis and inflammatory cytokines release in HUVEC. XIST expression was enhanced in HUVEC treated by ox-LDL, and its knockdown decreased cell apoptosis and inflammatory response in ox-LDL-treated cells. MiR-30c-5p was a target of XIST and its overexpression suppressed cell apoptosis and inflammatory response induced by ox-LDL, which was weakened by the introduction of XIST. PTEN was a target of miR-30c-5p, and its interference led to great inhibition of cell apoptosis and inflammatory response induced by ox-LDL in HUVEC, while this effect was attenuated by miR-30c-5p deficiency or XIST overexpression. CONCLUSIONS: XIST knockdown suppresses inflammatory response and apoptosis of HUVEC stimulated by ox-LDL by increasing miR-30c-5p and decreasing PTEN.