Postnatal N-acetylcysteine administration rescues impaired social behaviors and neurogenesis in Slc13a4 haploinsufficient mice.

BACKGROUND

Sulfate availability is crucial for the sulfonation of brain extracellular matrix constituents, membrane phospholipids, neurosteroids, and neurotransmitters. Observations from humans and mouse models suggest dysregulated sulfate levels may be associated with neurodevelopmental disorders, such as autism. However, the cellular mechanisms governing sulfate homeostasis within the developing or adult brain are not fully understood.

METHODS

We utilized a mouse model with a conditional allele for the sulfate transporter Slc13a4, and a battery of behavioral tests, to assess the effects of disrupted sulfate transport on maternal behaviors, social interactions, memory, olfaction, exploratory behavior, anxiety, stress, and metabolism. Immunohistochemistry examined neurogenesis within the stem cells niches.

FINDINGS

The sulfate transporter Slc13a4 plays a critical role in postnatal brain development. Slc13a4 haploinsufficiency results in significant behavioral phenotypes in adult mice, notably impairments in social interaction and long-term memory, as well as increased neurogenesis in the subventricular stem cell niche. Conditional gene deletion shows these phenotypes have a developmental origin, and that full biallelic expression of Slc13a4 is required only in postnatal development. Furthermore, administration of N-acetylcysteine (NAC) within postnatal window P14-P30 prevents the onset of phenotypes in adult Slc13a4 mice.

INTERPRETATION

Slc13a4 haploinsufficient mice highlight a requirement for adequate sulfate supply in postnatal development for the maturation of important social interaction and memory pathways. With evidence suggesting dysregulated sulfate biology may be a feature of some neurodevelopmental disorders, the utility of sulfate levels as a biomarker of disease and NAC administration as an early preventative measure should be further explored.