Subtype-specific regeneration of retinal ganglion cells following axotomy: effects of osteopontin and mTOR signaling.

ABSTRACT: In mammals, few retinal ganglion cells (RGCs) survive following axotomy, and even fewer regenerate axons. This could reflect differential extrinsic influences or the existence of subpopulations that vary in their responses to injury. We tested these alternatives by comparing responses of molecularly distinct subsets of mouse RGCs to axotomy. Survival rates varied dramatically among subtypes, with alpha-RGCs (αRGCs) surviving preferentially. Among survivors, αRGCs accounted for nearly all regeneration following downregulation of PTEN, which activates the mTOR pathway. αRGCs have uniquely high mTOR signaling levels among RGCs and also selectively express osteopontin (OPN) and receptors for the insulin-like growth factor 1 (IGF-1). Administration of OPN plus IGF-1 promotes regeneration as eff

SUBMITTER: Duan X 

PROVIDER: S-EPMC4391013 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature