Antioxidant Therapy With N-acetylcysteine for Learning and Motor Behavior in Children With Neurofibromatosis Type 1

Children with neurofibromatosis type 1 (NF1) commonly suffer from the effects of cognitive, behavioral, and motor impairments. At present there is no specific treatment for this NF1 complication. However, data from rodent models of NF1 along with uncontrolled clinical observations in children with NF1 suggest that the anti-oxidant, glutamate modulating compound N-Acetyl Cysteine (NAC) may reduce these impairments. Of particular interest is a murine study analyzing the central nervous system manifestations of NF1 at our institution. That study revealed a role for myelin-forming oligodendrocytes in the control of nitric oxide synthases (NOS) and their product, nitric oxide, in maintenance of brain structure and function, including regulation of behavior and motor control. Treating these mice with NAC corrected cellular and behavioral abnormalities. N-Acetyl Cysteine is available over the counter and has been used by thousands of individuals; moreover, it has shown some promise in clinical trials for psychiatric disorders. In order to better understand treatment mechanisms, and possibly predict long-term outcomes, the investigators propose concurrently to explore Specific Aim 1 (1.1, 1.2, and 1.3) exploratory potential disease biomarkers as outlined below. The primary outcome of this study is motor function rated with the Physical and Neurological Examination for Subtle Signs (PANESS), a validated scale that consistently demonstrates significant impairments in children with Attention Deficit Hyperactivity Disorder (ADHD), and which our preliminary data suggest may demonstrate more extreme problems in children with NF1. The first exploratory biomarker is motor system inhibitory physiology, measured using Transcranial Magnetic Stimulation (TMS). Preliminary measures in our NF1 population also show abnormalities similar to established findings in ADHD. The second exploratory biomarker is metabolomics profiling for the biomarker of oligodendrocyte dysfunction in NF1 participants: autotaxin. Preliminary data in our NF1 population showed specific signal abnormalities in the NF1 population compared to healthy controls. Therefore, the investigators propose to perform a double-blind placebo controlled, prospective, Phase IIa study to explore safety, tolerability, and efficacy of NAC on learning and motor behavior in children with NF1 aged 8 through 16 years old.