Lifespan effects of prenatal and perinatal opioid exposure on the brain's metabolic-epigenetic axis - PROJECT SUMMARY The rising opioid use rates have led to a significant increase in children exposed to opioids in utero, with adverse effects on both the placenta and developing brain. These effects include alterations in brain structures, including the cortex, hippocampus, and cerebellum. Affected children also have an increased susceptibility to neurodevelopmental disorders such as neonatal opioid withdrawal syndrome, as well as deficits in speech, cognition, and executive function. Despite these known effects, there are no neuroprotective treatments due to limited knowledge of the underlying molecular mechanisms. Here, we propose an innovative strategy to unravel the lifelong impact of prenatal opioid exposure on brain development. We will employ a well-characterized model of early-life morphine exposure to identify how opioid exposure during brain development disrupts the metabolic-epigenetic axis, potentially disrupting long-term cell type-specific maturation. In this model, previous bulk RNA sequencing has identified mitochondrial dysfunction, especially in the prenatal period. In other models of prenatal opioid exposure, mitochondrial dysfunction persists into adulthood and opioid exposure increases susceptibility to other brain injuries, like traumatic brain injury. Epigenetic patterns are frequently disrupted by metabolic anomalies. Therefore, we will explore the effects of opioid exposure on mitochondrial function and epigenetic regulation throughout the lifespan. In both the fetal and juvenile First, we will employ advanced in utero metabolic imaging with 4D-Oxywavelet MRI and molecular profiling to correlate mitochondrial dysfunction with single-nucleus joint transcriptomics and epigenomics in the placenta and different regions of the fetal brain (cortex, hippocampus, and cerebellum) after opioid exposure throughout gestation. Then, in exposure juvenile animals, we will perform brain region-specific mitochondrial function profiling in the cortex, hippocampus, and cerebellum. We will subsequently perform single- nucleus transcriptomic and epigenetic profiling in the same animals and brain regions. Both approaches will allow us to directly correlate the variability of metabolic disruption with cell type-specific molecular profiles, allowing us to dissect the interplay between metabolism and the epigenome in developmental opioid exposure at a resolution that has never occurred before. We hypothesize this approach will also provide insight into the potential biological underpinnings for the variability of neurodevelopmental outcomes seen from opioid exposure. By performing this comprehensive assessment of how the metabolic-epigenetic axis is disrupted by developmental opioid exposure, we will be able to identify novel, lifespan neuroprotective agents. Additionally, the approach is flexible and could be applied to study other prenatal exposures, including exposure to other substances, that disrupt the metabolic-epigenetic axis.
