The role of hippocampal niche exosomes in rat hippocampal neurogenesis after fimbria-fornix transection

Exosomes transfer signaling molecules such as proteins, lipids, and RNAs to facilitate cell–cell communication and play an important role in the stem cell microenvironment. In previous work, we demonstrated that rat fimbria–fornix transection (FFT) enhances neurogenesis from neural stem cells (NSCs) in the subgranular zone (SGZ). However, how neurogenesis is modulated after denervation remains unknown. Here, we investigated whether exosomes in a denervated hippocampal niche may affect neurogenesis. Using the FFT rat model, we extracted hippocampal exosomes and used RNA sequencing to identify noncoding RNA expression profiles. Overall design: The rat hippocampal tissue (denervated and untreated) was quickly harvested on ice. It was then digested with 0.125% trypsin at 37 °C for 30 min and the serum without exosomes was added to stop digestion. The Total Exosome Isolation Kit (from plasma) (Invitrogen, USA) was added to the supernatant after 4 °C, 3000g, 30 min centrifugation for an overnight stand. Then, after 4 °C, 10,000g, 1 h centrifugation, the precipitation was resuspended with 50 µl DPBS, and exosomes were harvested for the following experiments. high-throughput sequencing ofexosomes from hippocampal niche.