Maternal Immune Activation Leads to Mitochondrial Dysfunction and a Social Deficit in Offspring That Is Reversed by Nicotinamide Riboside.

Background

Maternal immune activation (MIA) during pregnancy is a known risk factor for several neurodevelopmental and psychiatric disorders, including schizophrenia. In rodent models, MIA is commonly induced using polyinosinic/polycytidylic acid (Poly(I/C)), a viral mimetic that activates Toll-like receptor 3 (TLR3) signaling and elicits an inflammatory response in both the dam and the fetuses. MIA results in various behavioral abnormalities in offspring, including deficits in social interaction. Recent studies have shown that MIA decreases the ability to maintain mitochondrial membrane potential (ΔΨm), the electrical component of the electrochemical gradient required for ATP production and alters mitochondrial protein expression in brain tissue isolated from adult offspring.

Methods

In the present study, we monitor ΔΨm non-invasively in vivo using a previously published bioluminescence probe in juvenile and adult MIA offspring. We then investigated gene expression in the medial prefrontal cortex of MIA offspring by analyzing a previously published RNA sequencing dataset in combination with MitoCarta3.0, a comprehensive inventory of genes involved in mitochondrial function. Finally, we tested the hypothesis that this mitochondrial dysfunction contributes to the behavioral deficits observed in MIA offspring.

Results

We have observed impaired ΔΨm maintenance in juvenile MIA offspring that persists into adulthood. Also, we found that MIA alters the expression of many genes associated with mitochondrial energy production. We demonstrated that nicotinamide riboside, a precursor to NAD+ known to restore ΔΨm, significantly attenuates MIA-induced social interaction deficits.

Conclusions

Together, these findings highlight mitochondrial function as a promising therapeutic target for symptoms associated with schizophrenia and support the potential for drug discovery aimed at enhancing mitochondrial health.