Longevity & AgingSynthetic circular RNA helps injured optic nerves regrow and protects retinal neurons in mice
Adult mammalian central nervous system neurons regenerate poorly, a problem that worsens with age. Researchers used computational modelling of single-cell RNA data from a peripheral nerve conditioning-lesion model to find microRNAs that control many regeneration-associated genes at once. They identified miR-340-5p, and inhibiting it promoted neurite growth in cultured neurons. They then built a synthetic circular RNA sponge (Circ-340-5p) to sequester this microRNA. In mice with optic nerve crush, it activated regeneration genes in retinal ganglion cells, along with PI3K and BDNF/TRKB signalling. Neuron survival improved shortly after injury but not at six weeks, while axon regeneration increased and kept improving over time. The work suggests a route to long-acting, microRNA-targeting therapies for optic nerve and other CNS injuries, though it remains preclinical.
