Therapeutic inhibition of mTORC2 rescues the behavioral and neurophysiological abnormalities associated with Pten-deficiency

Nat Med. 2019 Nov;25(11):1684-1690. doi: 10.1038/s41591-019-0608-y. Epub 2019 Oct 21.

Abstract

Dysregulation of the mammalian target of rapamycin (mTOR) signaling, which is mediated by two structurally and functionally distinct complexes, mTORC1 and mTORC2, has been implicated in several neurological disorders1-3. Individuals carrying loss-of-function mutations in the phosphatase and tensin homolog (PTEN) gene, a negative regulator of mTOR signaling, are prone to developing macrocephaly, autism spectrum disorder (ASD), seizures and intellectual disability2,4,5. It is generally believed that the neurological symptoms associated with loss of PTEN and other mTORopathies (for example, mutations in the tuberous sclerosis genes TSC1 or TSC2) are due to hyperactivation of mTORC1-mediated protein synthesis1,2,4,6,7. Using molecular genetics, we unexpectedly found that genetic deletion of mTORC2 (but not mTORC1) activity prolonged lifespan, suppressed seizures, rescued ASD-like behaviors and long-term memory, and normalized metabolic changes in the brain of mice lacking Pten. In a more therapeutically oriented approach, we found that administration of an antisense oligonucleotide (ASO) targeting mTORC2's defining component Rictor specifically inhibits mTORC2 activity and reverses the behavioral and neurophysiological abnormalities in adolescent Pten-deficient mice. Collectively, our findings indicate that mTORC2 is the major driver underlying the neuropathophysiology associated with Pten-deficiency, and its therapeutic reduction could represent a promising and broadly effective translational therapy for neurological disorders where mTOR signaling is dysregulated.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Brain / metabolism
  • Brain / pathology
  • Disease Models, Animal
  • Humans
  • Loss of Function Mutation / genetics
  • Mechanistic Target of Rapamycin Complex 1 / genetics
  • Mechanistic Target of Rapamycin Complex 2 / genetics*
  • Mice
  • Mice, Knockout
  • Nervous System Diseases / genetics*
  • Nervous System Diseases / metabolism
  • Nervous System Diseases / pathology
  • Oligonucleotides, Antisense / genetics
  • Oligonucleotides, Antisense / pharmacology
  • PTEN Phosphohydrolase / deficiency
  • PTEN Phosphohydrolase / genetics*
  • Rapamycin-Insensitive Companion of mTOR Protein / antagonists & inhibitors
  • Rapamycin-Insensitive Companion of mTOR Protein / genetics
  • TOR Serine-Threonine Kinases / genetics*
  • Tuberous Sclerosis Complex 1 Protein / genetics

Substances

  • Oligonucleotides, Antisense
  • Rapamycin-Insensitive Companion of mTOR Protein
  • Tsc1 protein, mouse
  • Tuberous Sclerosis Complex 1 Protein
  • rictor protein, mouse
  • mTOR protein, mouse
  • Mechanistic Target of Rapamycin Complex 1
  • Mechanistic Target of Rapamycin Complex 2
  • TOR Serine-Threonine Kinases
  • PTEN Phosphohydrolase
  • PTEN protein, human
  • Pten protein, mouse