【Animal Modeling】-Long non-coding RNA TUG1 regulates the mechanism of miR-137 involved in nerve injury in rats with focal cerebral ischemia

  Objective To investigate the role of long non-coding RNA (LncRNA) taurine up-regulated gene 1 (TUG1) regulating microRNA (miR)-137 involved in nerve injury in rats with focal cerebral ischemia.

  Methods Double luciferase was used to identify the target sites of miR-137 and TUG1; Longa suture method was used to establish a rat model of focal cerebral ischemia. -NC), si-TUG1 group (10 μL si-TUG1), si-TUG1+ anti-miR-NC group (10 μL each for si-TUG1 and anti-miR-NC), si-TUG1+anti-miR-137 group (10 μL each of si-TUG1 and anti-miR-137), 12 mice in each group. Another 12 were selected as the sham operation group. Once every 5 days, inject 3 times, and test on the 16th day. Real-time quantitative PCR (RT-qPCR) was used to detect the levels of TUG1 and miR-137 in the hippocampus; 2,3,5-triphenyltetrazolium chloride (TTC) staining was used to detect cerebral infarction; hematoxylin-eosin ( HE), Nissl staining to observe the morphology of hippocampal neurons; Western blot was used to detect protein tyrosine kinase 1 (JAK1), signal transducer and activator of transcription 1 (STAT1), B lymphocyte tumor in the hippocampus. -2 gene (BCL2), BCL2-associated X protein (BAX), caspase 3 (caspase3) protein levels.

  Results Starbase analysis found that miR-137 had a complementary binding site with TUG1, which was verified by dual luciferase. In the model group, the neuron levels in the hippocampus were disordered, the number of neurons decreased, the gap became larger, some neuron nuclei were pyknotic or dissolved, and the nucleoli disappeared, and the number of Nissl bodies decreased; the number of neurons in the si-TUG1 group decreased. Compared with the si-TUG1 group, the neuron morphology of the si-TUG1+anti-miR-137 group was severely damaged, the gap became larger and the number was reduced. Compared with the sham-operated group, the levels of TUG1, JAK1, STAT1, BAX and caspase3 protein in the hippocampus of the model group and si-NC group, the volume of cerebral infarction increased (P<0.05), the levels of miR-137 in the hippocampus, BCL2 Compared with the model group and si-NC group, the levels of TUG1, JAK1, STAT1, BAX and caspase3 in the hippocampus of the si-TUG1 group and si-TUG1+anti-miR-NC group were decreased (P<0.05). protein level, the volume of cerebral infarction decreased (P<0.05), the level of miR-137 and BCL2 protein in hippocampus increased (P<0.05); Compared with the NC group, the si-TUG1+anti-miR-137 group had higher levels of TUG1 in the hippocampus, protein levels of JAK1, STAT1, BAX, and caspase3, and increased cerebral infarction volume (P<0.05). BCL2 protein level decreased (P<0.05).

  Conclusion Interfering with TUG1 can up-regulate miR-137 to alleviate neuronal morphology and apoptosis in rats with focal cerebral ischemia, thereby protecting nerve damage.