Tyrosine-mutated AAV2-mediated shRNA silencing of PTEN promotes axon regeneration of adult optic nerve

PLoS One. 2017 Mar 21;12(3):e0174096. doi: 10.1371/journal.pone.0174096. eCollection 2017.

Abstract

Activating PI3K/AKT/mTOR signaling pathway via deleting phosphatase and tensin homolog (PTEN) has been confirmed to enhance intrinsic growth capacity of neurons to facilitate the axons regeneration of central nervous system after injury. Considering conditional gene deletion is currently not available in clinical practice, we exploited capsid residue tyrosine 444 to phenylalanine mutated single-stranded adeno-associated virus serotype 2 (AAV2) as a vector delivering short hairpin RNA to silence PTEN to promote retinal ganglion cells (RGCs) survival and axons regeneration in adult rat optic nerve axotomy paradigm. We found that mutant AAV2 displayed higher infection efficiency to RGCs and Müller cells by intravitreal injection, mediated PTEN suppression, resulted in much more RGCs survival and more robust axons regeneration compared with wild type AAV2, due to the different extent of the mTOR complex-1 activation and glutamate aspartate transporter (GLAST) regulation. These results suggest that high efficiency AAV2-mediated PTEN knockdown represents a practicable therapeutic strategy for optic neuropathy.

MeSH terms

  • Amino Acid Transport System X-AG / metabolism
  • Animals
  • Axons / metabolism*
  • Dependovirus / genetics
  • Ependymoglial Cells / physiology
  • Female
  • Genetic Therapy / methods
  • Optic Nerve / metabolism*
  • Optic Nerve Diseases / genetics
  • Optic Nerve Diseases / therapy*
  • PTEN Phosphohydrolase / genetics*
  • Phosphatidylinositol 3-Kinases / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • RNA Interference
  • RNA, Small Interfering / genetics
  • Rats
  • Rats, Sprague-Dawley
  • Regeneration / genetics*
  • Retinal Ganglion Cells / physiology
  • Signal Transduction
  • TOR Serine-Threonine Kinases / metabolism

Substances

  • Amino Acid Transport System X-AG
  • RNA, Small Interfering
  • mTOR protein, rat
  • Proto-Oncogene Proteins c-akt
  • TOR Serine-Threonine Kinases
  • PTEN Phosphohydrolase
  • Pten protein, rat

Grants and funding

This work was supported by the Research Foundation of Jiangsu Provincial Commission of Health and Family Planning (NO.H201653, http://www.jswst.gov.cn/jsswshjhsywyh/). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.