title: Targeting Translation Control with p70 S6 Kinase 1 Inhibitors to Reverse Phenotypes in Fragile X Syndrome Mice.
abstract: Aberrant neuronal translation is implicated in the etiology of numerous brain disorders. Although mTORC1-p70 ribosomal S6 kinase 1 (S6K1) signaling is critical for translational control, pharmacological manipulation in vivo has targeted exclusively mTORC1 due to the paucity of specific inhibitors to S6K1. However, small molecule inhibitors of S6K1 could potentially ameliorate pathological phenotypes of diseases, which are based on aberrant translation and protein expression. One such condition is fragile X syndrome (FXS), which is considered to be caused by exaggerated neuronal translation and is the most frequent heritable cause of autism spectrum disorder (ASD). To date, potential therapeutic interventions in FXS have focused largely on targets upstream of translational control to normalize FXS-related phenotypes. Here we test the ability of two S6K1 inhibitors, PF-4708671 and FS-115, to normalize translational homeostasis and other phenotypes exhibited by FXS model mice. We found that although the pharmacokinetic profiles of the two S6K1 inhibitors differed, they overlapped in reversing multiple disease-associated phenotypes in FXS model mice including exaggerated protein synthesis, inappropriate social behavior, behavioral inflexibility, altered dendritic spine morphology, and macroorchidism. In contrast, the two inhibitors differed in their ability to rescue stereotypic marble-burying behavior and weight gain. These findings provide an initial pharmacological characterization of the impact of S6K1 inhibitors in vivo for FXS, and have therapeutic implications for other neuropsychiatric conditions involving aberrant mTORC1-S6K1 signaling.
authors.affiliation: Center for Neural Science, New York University, New York, NY, USA.
authors.forename: Aditi
authors.initials: A
authors.lastname: Bhattacharya
authors.affiliation: Center for Neural Science, New York University, New York, NY, USA.
authors.forename: Maggie
authors.initials: M
authors.lastname: Mamcarz
authors.affiliation: Center for Neural Science, New York University, New York, NY, USA.|New York University Neuroscience Institute, New York University Langone Medical Center, New York, NY, USA.
authors.forename: Caitlin
authors.initials: C
authors.lastname: Mullins
authors.affiliation: Center for Neural Science, New York University, New York, NY, USA.|Department of Psychology, Hunter College, City University of New York, New York, NY, USA.
authors.forename: Ayesha
authors.initials: A
authors.lastname: Choudhury
authors.affiliation: Sentinel Oncology, Cambridge, UK.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Boyle
authors.affiliation: Autism Speaks, Boston, MA, USA.
authors.forename: Daniel G
authors.identifier: 0000-0003-4637-8992
authors.initials: DG
authors.lastname: Smith
authors.affiliation: Sentinel Oncology, Cambridge, UK.
authors.forename: David W
authors.initials: DW
authors.lastname: Walker
authors.affiliation: Center for Neural Science, New York University, New York, NY, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Klann
mesh_terms: D000818:Animals; D000067877:Autism Spectrum Disorder / Q000517:prevention & control / Q000523:psychology; D001522:Behavior, Animal / Q000187:drug effects*; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D049229:Dendritic Spines / Q000187:drug effects / Q000473:pathology; D004195:Disease Models, Animal; D005106:Exploratory Behavior / Q000187:drug effects; D005260:Female; D005600:Fragile X Syndrome / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects*; D007093:Imidazoles / Q000008:administration & dosage*; D008297:Male; D008810:Mice, Inbred C57BL; D010641:Phenotype; D010766:Phosphorylation; D010879:Piperazines / Q000008:administration & dosage*; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage* / Q000494:pharmacology*; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000037:antagonists & inhibitors*; D012919:Social Behavior
chemical_list: D007093:Imidazoles; C552719:PF-4708671; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D038762:Ribosomal Protein S6 Kinases, 70-kDa