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Administration of ethanol to rodents during the synaptogenesis period induces extensive apoptotic neurodegeneration in the developing brain. This neurotoxicity may explain the reduced brain mass and neurobehavioral disturbances in human Fetal Alcohol Syndrome (FAS). Here, we report binge-like exposure of infant mice to ethanol on a single postnatal day triggered apoptotic death of neurons from diencephalic structures that comprise an extended hippocampal circuit important for spatial learning and memory. The ethanol exposure paradigm yielding these neuronal losses caused profound impairments in spatial learning and memory at 1 month of age. This impairment was significantly attenuated during subsequent development, indicating recovery of function. Recovery was not associated with increased neurogenesis, suggesting plastic reorganization of neuronal networks compensated for early neuronal losses. We hypothesize that neuroapoptotic damage in homologous regions of human brain underlies cognitive deficits in FAS and the human brain of FAS victims has a similar capacity to effect functional recovery.

Abstract: Spinocerebellar ataxia 27 (SCA27) is a recently described syndrome characterized by impaired cognitive abilities and a slowly progressive ataxia. SCA27 is caused by an autosomal dominant missense mutation in Fibroblast Growth Factor 14 (FGF14). Mice lacking FGF14 (Fgf14 −/− mice) have impaired sensorimotor functions, ataxia and paroxysmal dyskinesia, a phenotype that led to the discovery of the human mutation. Here we extend the similarities between Fgf14 −/− mice and FGF14(F145S) humans by showing that Fgf14 −/− mice exhibit reliable acquisition (place learning) deficits in the Morris water maze. This cognitive deficit appears to be independent of sensorimotor disturbances and relatively selective since Fgf14 −/− mice performed similarly to wild type littermates during cued water maze trials and on conditioned fear and passive avoidance tests. Impaired theta burst initiated long-term synaptic potentiation was also found in hippocampal slices from Fgf14 −/− mice. These results suggest a role for FGF14 in certain spatial learning functions and synaptic plasticity. [Copyright &y& Elsevier]