A novel function and mechanism of ischemia-induced retinal astrocyte-derived exosomes for RGC apoptosis of ischemic retinopathy

• Main Authors: Xiaoyuan Ye (Author), Yunfei Liu (Author), Congying Chen (Author), Yimeng Sun (Author), Fan Li (Author), Yunzhao Fu (Author), Jiawen Luo (Author), Lishi Su (Author), Wei Chi (Author)
• Format: Book
• Published: Elsevier, 2024-06-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

Retinal ischemia is a common clinical event leading to retinal ganglion cell (RGC) death, resulting in irreversible vision loss. In the retina, glia-neuron communication is crucial for multiple functions and homeostasis. Extracellular vesicles, notably exosomes, play a critical role. The functions and mechanisms of retinal astrocyte-secreted exosomes remain unclear. Here, we isolated astrocyte-derived exosomes under hypoxia or normoxia and explored their role in an in vivo retinal ischemia-reperfusion (RIR) model. We found that hypoxia triggered astrocytes to produce a significantly increased number of exosomes, which could be internalized by RGCs in vivo or in vitro. Also, in the RIR model, the hypoxia-induced exosomes ameliorated the RIR injury and suppressed the RGC apoptosis. Furthermore, microRNA sequencing of retinal astrocyte-secreted exosomes revealed different patterns of exosomal miRNAs under hypoxia, particularly enriched with miR-329-5p. We verified that miR-329-5p was specifically bound to mitogen-activated protein kinase 8 mRNA, and subsequent JNK-pathway molecules were downregulated. We anticipated that the miR-329-5p/JNK pathway is a key to suppressing RGC apoptosis and preventing RIR injury. Such findings provided insights into the therapeutic potential of hypoxia-induced astrocyte-secreted exosomes and the miR-329-5p for treating retina ischemic diseases.

Item Description

2162-2531
10.1016/j.omtn.2024.102209