Inhibition of LOXL1-AS1 alleviates oxidative low-density lipoprotein induced angiogenesis via downregulation of miR-590-5p mediated KLF6/VEGF signaling pathway.

Increasing evidences have confirmed that long non-coding RNA LOXL1-AS1 functions in multiple human diseases. Here, we aim to explore the function and mechanism of LOXL1-AS1 in modulating oxidized low-density lipoprotein (ox-LDL)-induced angiogenesis of endothelial cells (ECs). Presently, we found that LOXL1-AS1 and KLF6 were upregulated in ECs treated by Ox-LDL in a dose- and time-dependent manner while miR-590-5p was downregulated. Overexpression of LOXL1-AS1 aggravated Ox-LDL mediated ECs proliferation and migration, and promoted angiogenesis both in vitro and in vivo. On the contrary, enhancing miR-590-5p or inhibiting LOXL1-AS1 level led to suppressive effects on the proliferation, migration and angiogenesis of ECs. Moreover, LOXL1-AS1 upregulation promoted the expression of vascular endothelial growth factor (VEGF), MMPs (including MMP2, MMP9 and MMP14) and also activated VEGF/VEGFR2/PI3K/Akt/eNOS pathway. Mechanistically, LOXL1-AS1 works as a competitive endogenous RNA (ceRNA) by sponging miR-590-5p, which targeted at the 3'-untranslated region (3'UTR) of KLF6. Additionally, the proliferation, migration and angiogenesis of ECs were elevated following KLF6 upregulation. By detecting the expression of LOXL1-AS1 and miR-590-5p in the serum of healthy donors and atherosclerosis patients, it was found that LOXL1-AS1 was upregulated in atherosclerosis patients (compared with healthy donors) and had a negative relationship with miR-590-5p. Taken together, LOXL1-AS1 promoted Ox-LDL induced angiogenesis via regulating miR-590-5p-modulated KLF6/VEGF signaling pathway. The LOXL1-AS1-miR-590-5p axis exerts a novel role in the progression of atherosclerosis.