title: Alterations of GABAergic signaling in autism spectrum disorders.
abstract: Autism spectrum disorders (ASDs) comprise a heterogeneous group of pathological conditions, mainly of genetic origin, characterized by stereotyped behavior, marked impairment in verbal and nonverbal communication, social skills, and cognition. Interestingly, in a small number of cases, ASDs are associated with single mutations in genes encoding for neuroligin-neurexin families. These are adhesion molecules which, by regulating transsynaptic signaling, contribute to maintain a proper excitatory/inhibitory (E/I) balance at the network level. Furthermore, GABA, the main inhibitory neurotransmitter in adult life, at late embryonic/early postnatal stages has been shown to depolarize and excite targeted cell through an outwardly directed flux of chloride. The depolarizing action of GABA and associated calcium influx regulate a variety of developmental processes from cell migration and differentiation to synapse formation. Here, we summarize recent data concerning the functional role of GABA in building up and refining neuronal circuits early in development and the molecular mechanisms regulating the E/I balance. A dysfunction of the GABAergic signaling early in development leads to a severe E/I unbalance in neuronal circuits, a condition that may account for some of the behavioral deficits observed in ASD patients.
authors.affiliation: Neurobiology Sector and IIT Unit, International School for Advanced Studies (SISSA), Via Bonomea 265, 34136 Trieste, Italy.
authors.forename: Rocco
authors.initials: R
authors.lastname: Pizzarelli
authors.forename: Enrico
authors.initials: E
authors.lastname: Cherubini
mesh_terms: D001921:Brain / Q000503:physiopathology*; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000503:physiopathology*; D006801:Humans; D009433:Neural Inhibition / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
chemical_list: D005680:gamma-Aminobutyric Acid