Study of lncRNA TUG1/miR-320 in EPC Transplantation to Improve Lower Limb Ischemia and Promote Angiogenesis in Mice

Abstract To The aim of the current study was to investigate the changes in lncRNA TUG1/miR-320 and related proteins with ischaemic time in an ischemia model. A nude mouse model of lower limb ischemia was established by ligating the femoral artery, and laser Doppler measurements were used to demonstrate the successful establishment of the ischemia model. The cells were extracted from the bone marrow of nude mice, and the proliferation, migration and vascular-forming ability of the cells were analysed. When transplanted into ischemia model mice, blood flow measurements indicated that EPCs can speed up blood flow recovery. The results of HE staining indicated an improvement in inflammatory damage, and immunohistochemistry revealed an increase in capillaries. RT-PCR and Western blot experiments showed that the improvement of ischemia was related to an increase in lncRNA TUG1 and a decrease in miR-320 and that the expression of the related downstream proteins STAT3, VEGFR-2, Wnt-5a and β-catenin increased gradually. These changes promoted an increase in capillaries, the recovery of blood flow, and the improvement of muscle damage. Therefore, EPC transplantation can improve the inflammatory response of lower limb muscles by increasing the expression of lncRNA TUG1 and thereby accelerate the recovery of ischaemic limbs.