title: Sex Is a major determinant of neuronal dysfunction in neurofibromatosis type 1.
abstract: OBJECTIVE
  Children with neurofibromatosis-1 (NF1) are at risk for developing numerous nervous system abnormalities, including cognitive problems and brain tumors (optic pathway glioma). Currently, there are few prognostic factors that predict clinical manifestations or outcomes in patients, even in families with an identical NF1 gene mutation. In this study, we leveraged Nf1 genetically engineered mice (GEM) to define the potential role of sex as a clinically relevant modifier of NF1-associated neuronal dysfunction.
  
  
  METHODS
  Deidentified clinical data were analyzed to determine the impact of sex on optic glioma-associated visual decline in children with NF1. In addition, Nf1 GEM were employed as experimental platforms to investigate sexually dimorphic differences in learning/memory, visual acuity, retinal ganglion cell (RGC) death, and Nf1 protein (neurofibromin)-regulated signaling pathway function (Ras activity, cyclic adenosine monophosphate [cAMP], and dopamine levels).
  
  
  RESULTS
  Female patients with NF1-associated optic glioma were twice as likely to undergo brain magnetic resonance imaging for visual symptoms and 3× more likely to require treatment for visual decline than their male counterparts. As such, only female Nf1 GEM exhibited a decrement in optic glioma-associated visual acuity, shorter RGC axons, and attenuated cAMP levels. In contrast, only male Nf1 GEM showed spatial learning/memory deficits, increased Ras activity, and reduced dopamine levels.
  
  
  CONCLUSIONS
  Collectively, these observations establish sex as a major prognostic factor underlying neuronal dysfunction in NF1, and suggest that sex should be considered when interpreting future preclinical and clinical study results.
authors.affiliation: Departments of Neurology, Washington University School of Medicine, Box 8111, 660 South Euclid Avenue, St Louis, MO.
authors.forename: Kelly A
authors.initials: KA
authors.lastname: Diggs-Andrews
authors.forename: Jacquelyn A
authors.initials: JA
authors.lastname: Brown
authors.forename: Scott M
authors.initials: SM
authors.lastname: Gianino
authors.forename: Joshua B
authors.initials: JB
authors.lastname: Rubin
authors.forename: David F
authors.initials: DF
authors.lastname: Wozniak
authors.forename: David H
authors.initials: DH
authors.lastname: Gutmann
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology; D002648:Child; D004298:Dopamine / Q000378:metabolism; D051937:Dopamine and cAMP-Regulated Phosphoprotein 32 / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics; D005904:Glial Fibrillary Acidic Protein / Q000235:genetics; D006624:Hippocampus / Q000378:metabolism; D006801:Humans; D007859:Learning Disabilities / Q000209:etiology* / Q000235:genetics; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009456:Neurofibromatosis 1 / Q000150:complications* / Q000473:pathology; D025542:Neurofibromin 1 / Q000235:genetics; D020339:Optic Nerve Glioma / Q000235:genetics; D012737:Sex Factors; D013028:Space Perception / Q000502:physiology; D014786:Vision Disorders / Q000209:etiology*
chemical_list: D051937:Dopamine and cAMP-Regulated Phosphoprotein 32; D005904:Glial Fibrillary Acidic Protein; D025542:Neurofibromin 1; C497929:Ppp1r1b protein, mouse; D004298:Dopamine