title: Pharmacological stimulation of the brain serotonin receptor 7 as a novel therapeutic approach for Rett syndrome.
abstract: Rett syndrome (RTT) is a rare neurodevelopmental disorder, characterized by severe behavioral and physiological symptoms. Mutations in the methyl CpG-binding protein 2 gene (MECP2) cause >95% of classic cases, and currently there is no cure for this devastating disorder. The serotonin receptor 7 (5-HT7R) is linked to neuro-physiological regulation of circadian rhythm, mood, cognition, and synaptic plasticity. We presently report that 5-HT7R density is consistently reduced in cortical and hippocampal brain areas of symptomatic MeCP2-308 male mice, a RTT model. Systemic repeated treatment with LP-211 (0.25 mg/kg once/day for 7 days), a brain-penetrant selective 5-HT7R agonist, was able to rescue RTT-related defective performance: anxiety-related profiles in a Light/Dark test, motor abilities in a Dowel test, the exploratory behavior in the Marble Burying test, as well as memory in the Novelty Preference task. In the brain of RTT mice, LP-211 also reversed the abnormal activation of PAK and cofilin (key regulators of actin cytoskeleton dynamics) and of the ribosomal protein (rp) S6, whose reduced activation in MECP2 mutant neurons by mTOR is responsible for the altered protein translational control. Present findings indicate that pharmacological targeting of 5-HT7R improves specific behavioral and molecular manifestations of RTT, thus representing a first step toward the validation of an innovative systemic treatment. Beyond RTT, the latter might be extended to other disorders associated with intellectual disability.
authors.affiliation: Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Bianca
authors.initials: B
authors.lastname: De Filippis
authors.affiliation: Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Nativio
authors.affiliation: Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Fabbri
authors.affiliation: Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Ricceri
authors.affiliation: Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Walter
authors.initials: W
authors.lastname: Adriani
authors.affiliation: Department of Pharmacy, University of Bari 'A Moro', Bari, Italy.
authors.forename: Enza
authors.initials: E
authors.lastname: Lacivita
authors.affiliation: Department of Pharmacy, University of Bari 'A Moro', Bari, Italy.
authors.forename: Marcello
authors.initials: M
authors.lastname: Leopoldo
authors.affiliation: Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Passarelli
authors.affiliation: 1] Department of Psychology, Section of Neuroscience, Sapienza University of Rome, Rome, Italy [2] European Center for Brain Research (CERC)/IRCCS Santa Lucia Foundation, Rome, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Fuso
authors.affiliation: Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Laviola
mesh_terms: D051339:Actin Depolymerizing Factors / Q000378:metabolism; D000818:Animals; D001007:Anxiety / Q000188:drug therapy / Q000503:physiopathology; D001921:Brain / Q000187:drug effects* / Q000503:physiopathology; D004195:Disease Models, Animal; D005106:Exploratory Behavior / Q000187:drug effects / Q000502:physiology; D008297:Male; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D010879:Piperazines / Q000494:pharmacology*; D011619:Psychotropic Drugs / Q000494:pharmacology*; D011985:Receptors, Serotonin / Q000378:metabolism*; D015518:Rett Syndrome / Q000188:drug therapy* / Q000503:physiopathology; D038601:Ribosomal Protein S6 / Q000378:metabolism; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*; D054462:p21-Activated Kinases / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D051339:Actin Depolymerizing Factors; C573815:N-(4-cyanophenylmethyl)-4-(2-diphenyl)-1-piperazinehexanamide; D010879:Piperazines; D011619:Psychotropic Drugs; D011985:Receptors, Serotonin; D038601:Ribosomal Protein S6; D017366:Serotonin Receptor Agonists; C448579:ribosomal protein S6, mouse; C104425:serotonin 7 receptor; D054462:p21-Activated Kinases; D020741:rho GTP-Binding Proteins