An antioxidant therapy elicits distinct transcriptome responses in 22q11-deleted upper layer cortical projection neurons

We characterized in vitro and in vivo responses to the antioxidant N-acetyl cysteine (NAC), which in the 22q11.2 Deletion Syndrome LgDel mouse model restores growth and connectivity of developing upper layer cortical projection neurons (Layer 2/3 PNs) and improves cognitive performance. NAC ameliorates L 2/3 PN developmental pathology without restoring wild type (WT) growth patterns or expression levels of downstream targets of 22q11-deleted genes. Instead, novel neuronal growth and antioxidant defense genes are differentially expressed compared to LgDel or WT: some generally NAC-regulated, others responsive only in the context of 22q11 deletion. NAC also elicits novel growth and antioxidant defense gene expression in differentiating 22q11-deleted L 2/3 PNs in postnatal LgDel mouse cortex rather than restoring 22q11 downstream targets to WT levels; however, these L 2/3 PN-selective in vivo changes differ substantially from those in primary culture. Thus, the NAC therapeutic response that diminishes oxidative stress-related L 2/3 PN developmental circuit and behavioral pathology due to 22q11 deletion has a distinct in vivo signature.