Sex-specific hippocampus-dependent cognitive deficits and increased neuronal autophagy in DEspR haploinsufficiency in mice

Physiol Genomics. 2008 Nov 12;35(3):316-29. doi: 10.1152/physiolgenomics.00044.2008. Epub 2008 Sep 9.

Abstract

Aside from abnormal angiogenesis, dual endothelin-1/VEGF signal peptide-activated receptor deficiency (DEspR(-/-)) results in aberrant neuroepithelium and neural tube differentiation, thus elucidating DEspR's role in neurogenesis. With the emerging importance of neurogenesis in adulthood, we tested the hypothesis that nonembryonic-lethal DEspR haploinsufficiency (DEspR(+/-)) perturbs neuronal homeostasis, thereby facilitating aging-associated neurodegeneration. Here we show that, in male mice only, DEspR-haploinsufficiency impaired hippocampus-dependent visuospatial and associative learning and induced noninflammatory spongiform changes, neuronal vacuolation, and loss in the hippocampus, cerebral cortex, and subcortical regions, consistent with autophagic cell death. In contrast, DEspR(+/-) females exhibited better cognitive performance than wild-type females and showed absence of neuropathological changes. Signaling pathway analysis revealed DEspR-mediated phosphorylation of activators of autophagy inhibitor mammalian target of rapamycin (mTOR) and dephosphorylation of known autophagy inducers. Altogether, the data demonstrate DEspR-mediated diametrical, sex-specific modulation of cognitive performance and autophagy, highlight cerebral neuronal vulnerability to autophagic dysregulation, and causally link DEspR haploinsufficiency with increased neuronal autophagy, spongiosis, and cognitive decline in mice.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Autophagy / genetics
  • Autophagy / physiology*
  • Behavior, Animal / physiology
  • Cognition Disorders / genetics*
  • Cognition Disorders / pathology
  • Cognition Disorders / physiopathology
  • Female
  • Hippocampus / metabolism*
  • Hippocampus / pathology
  • Male
  • Maze Learning / physiology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mutation
  • Neurons / metabolism*
  • Neurons / pathology
  • Receptors, Angiotensin / genetics
  • Receptors, Endothelin / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sex Factors
  • Social Behavior

Substances

  • Receptors, Angiotensin
  • Receptors, Endothelin