[Identification of potential traumatic spinal cord injury related circular RNA-microRNA networks by sequence analysis]

Exosomes Secreted from circZFHX3-modified Mesenchymal Stem Cells Repaired Spinal Cord Injury Through mir-16-5p/IGF-1 in Mice

BACKGROUND

Spinal cord injury (SCI) is a devastating neurological event that leads to severe motor and sensory dysfunction. Exosome-mediated transfer of circular RNAs (circRNAs) was associated with SCI, and exosomes have been reported to be produced by mesenchymal stem cells (MSCs). This study is designed to explore the mechanism of exosomal circZFHX3 on LPS-induced MSCs injury in SCI.

METHODS

Exosomes were detected by transmission electron microscope and nanoparticle tracking analysis. CD9, CD63, CD81, and TSC101, B-cell lymphoma-2 (Bcl-2), Bcl-2 related X protein (Bax), Cleaved caspase 3, and Insulin-like growth factor 1 (IGF-1) protein levels were measured by western blot assay. CircZFHX3, microRNA-16-5p (miR-16-5p), and IGF-1 level were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell viability and apoptosis were detected by Cell Counting Kit-8 (CCK-8) and flow cytometry assay. Levels of IL-1β, IL-6, and TNF-α were assessed using Enzyme-linked immunosorbent assays (ELISA). ROS, LDH, and SOD levels were measured by the special kits. The binding between miR-16-5p and circZFHX3 or IGF-1 was predicted by Starbase and DianaTools and then verified by a dual-luciferase reporter and RNA Immunoprecipitation (RIP) assays. The biological role of exosomal circZFHX3 on SCI mice was examined in vivo.

RESULTS

CircZFHX3 and IGF-1 were decreased, and miR-16-5p was increased in SCI mice. Also, exosomal circZFHX3 boosted cell viability and repress apoptosis, inflammation, and oxidative stress in LPS-treated BV-2 cells in vitro. Mechanically, circZFHX3 acted as a sponge of miR-16-5p to regulate IGF-1 expression. Exosomal circZFHX3 reduced cell injury of SCI in vivo.

CONCLUSIONS

Exosomal circZFHX3 inhibited LPS-induced BV-2 cell injury partly by regulating the miR-16-5p/ IGF-1 axis, hinting at a promising therapeutic strategy for the SCI treatment.

CircSERPINA3 regulates SERPINA3-mediated apoptosis, autophagy and aerobic glycolysis of prostate cancer cells by competitively binding to MiR-653-5p and recruiting BUD13

BACKGROUND

Prostate cancer (PCa) belongs to an epithelial malignancy that occurs in the prostate gland and is the most common malignancy of the male genitourinary system. Referring to related literature, circSERPINA3 has been reported to be up-regulated in PCa. However, its biological function remains unclear.

PURPOSE

This study aimed to reveal the specific role and relevant molecular mechanism of circSERPINA3 in PCa.

METHODS

RT-qPCR was used to examine gene expression and functional analyses were conducted to verify the effect of circSERPINA3 on cell apoptosis, autophagy and aerobic glycolysis in PCa cells. Mechanism assays were applied to evaluate the relationship among circSERPINA3/miR-653-5p/SERPINA3/BUD13.

RESULTS

CircSERPINA3 was verified to be up-regulated in PCa cells and to inhibit cell apoptosis while promoting aerobic glycolysis and autophagy in PCa cells. CircSERPINA3 and SERPINA3 were also testified to bind to miR-653-5p through a line of mechanism experiments. Moreover, it was discovered that circSERPINA3 could stabilize SERPINA3 mRNA via recruiting BUD13. Additionally, SERPINA3 was verified to inhibit cell apoptosis, while promoting aerobic glycolysis and autophagy in PCa cells.

CONCLUSIONS

Our study suggested that circSERPINA3 regulated apoptosis, autophagy and aerobic glycolysis of PCa cells by competitively binding to miR-653-5p and recruiting BUD13.

New Insight of Circular RNAs' Roles in Central Nervous System Post-Traumatic Injury

The central nervous system (CNS) post-traumatic injury can cause severe nerve damage with devastating consequences. However, its pathophysiological mechanisms remain vague. There is still an urgent need for more effective treatments. Circular RNAs (circRNAs) are non-coding RNAs that can form covalently closed RNA circles. Through second-generation sequencing technology, microarray analysis, bioinformatics, and other technologies, recent studies have shown that a number of circRNAs are differentially expressed after traumatic brain injury (TBI) or spinal cord injury (SCI). These circRNAs play important roles in the proliferation, inflammation, and apoptosis in CNS post-traumatic injury. In this review, we summarize the expression and functions of circRNAs in CNS in recent studies, as well as the circRNA–miRNA–mRNA interaction networks. The potential clinical value of circRNAs as a therapeutic target is also discussed.