Perinatal fluoxetine exposure results in social deficits and reduced monoamine oxidase gene expression in mice.

Perinatal antidepressant drug exposure increases risk for autism spectrum disorder, yet the molecular and neurobehavioral effects of maternal antidepressant drug use on offspring remain poorly understood. In this study, we administered the selective serotonin reuptake inhibitor (SSRI) fluoxetine non-invasively to female mice throughout gestation and early lactation, and then examined social interaction behaviors in offspring. In addition, we measured whole brain gene expression levels of monoamine oxidase A (MAOA), the primary metabolizing enzyme for serotonin. We found deficits in sociability and social novelty-seeking behavior in the juvenile offspring of SSRI-treated mice, and these behaviors persisted into young adulthood. Furthermore, we found decreased MAOA expression in the brains of offspring of SSRI-treated mice. Our findings suggest that exposure to antidepressants during the prenatal and early postnatal period may negatively affect social development. Moreover, reduced MAOA expression may play a role in the mechanistic pathway linking SSRI exposure and behavioral deficits symptomatic of autism.

Expression of the G72/G30 gene in transgenic mice induces behavioral changes.

The G72/G30 gene complex is a candidate gene for schizophrenia and bipolar disorder. However, G72 and G30 mRNAs are expressed at very low levels in human brain, with only rare splicing forms observed. We report here G72/G30 expression profiles and behavioral changes in a G72/G30 transgenic mouse model. A human BAC clone containing the G72/G30 genomic region was used to establish the transgenic mouse model, on which gene expression studies, western blot and behavioral tests were performed. Relative to their minimal expression in humans, G72 and G30 mRNAs were highly expressed in the transgenic mice, and had a more complex splicing pattern. The highest G72 transcript levels were found in testis, followed by cerebral cortex, with very low or undetectable levels in other tissues. No LG72 (the long putative isoform of G72) protein was detected in the transgenic mice. Whole-genome expression profiling identified 361 genes differentially expressed in transgenic mice compared with wild-type, including genes previously implicated in neurological and psychological disorders. Relative to wild-type mice, the transgenic mice exhibited fewer stereotypic movements in the open field test, higher baseline startle responses in the course of the prepulse inhibition test, and lower hedonic responses in the sucrose preference test. The transcriptome profile changes and multiple mouse behavioral effects suggest that the G72 gene may play a role in modulating behaviors relevant to psychiatric disorders.