Hypoxia-inducible factor-1 α regulates PI3K/AKT signaling through microRNA-32-5p/PTEN and affects nucleus pulposus cell proliferation and apoptosis

Exp Ther Med. 2021 Jun;21(6):646. doi: 10.3892/etm.2021.10078. Epub 2021 Apr 18.ABSTRACTIntervertebral disc degeneration and resulting low back pain arises from the programmed apoptosis of nucleus pulposus cells (NPCs). Recent studies show that hypoxia-inducible factor-1α plays a vital role in the etiology and pathogenesis of disc degeneration. However, the underlying mechanism of HIF-1α in NPCs is unclear. The present study identified 994 significant differentially expressed miRNAs by analyzing microarray data downloaded from the Gene Expression Omnibus database. MicroRNA(miR)-32-5p expression was 2.81-fold upregulated in NPCs compared with that of the healthy control tissues (P<0.05). A total of 331 significant differentially expressed mRNAs were identified, and PTEN was downregulated in NPCs of non-degenerative disc tissues from young patients. miR-32-5p was predicted to target the PTEN 3'-untranslated region (UTR). To confirm these results, in-vitro experiments investigating the molecular function of miR-32-5p and PTEN were performed. Furthermore, hypoxia induced miR-32-5p and PTEN expression. HIF-1α inhibited NPC proliferation and promoted cell apoptosis by regulating miR-32-5p and PTEN. miR-32-5p promoted NPC proliferation and decreased cell apoptosis. Next, it was verified whether miR-32-5p targeted the PTEN 3'-UTR using dual-luciferase reporter assays. Finally, it was observed that PI3K/AKT/mTOR signaling pathway was upregulated by a miR-32-5p mimic, which impro...
Source: Experimental and Therapeutic Medicine - Category: General Medicine Authors: Source Type: research