Prenatal alcohol exposure induces circular and linear long non-coding RNAs, and protein-coding genes linked to proinflammatory neuroimmune function, promoting nerve injury-induced allodynia following morphine treatment.

Prenatal alcohol exposure (PAE) exerts lingering effects on neuroimmune function. Based on existing literature on overlapping neuroimmune actions of PAE and opioid pain therapies, here, we examined pain sensitivity (allodynia) in adult male PAE mice following opioid (morphine) treatment. Using a previously characterized model of minor nerve injury, we show that morphine treatment promotes allodynia in PAE mice, not in control mice. This study characterized spinal transcriptomics and explored potential roles of non-coding RNAs (ncRNAs) underlying this paradoxical effect of morphine in PAE mice. Utilizing next-generation bulk RNA sequencing, we generated a comprehensive profile of spinal mRNAs, circular RNAs (circRNAs), and linear long non-coding RNAs (lncRNAs) from morphine-treated allodynic PAE mice. This unbiased approach identified endogenous immune activators (Tcf7l2, Dnaj1, Hmgb1, Hsph1) and the involvement of oxidative stress, hemoglobin genes in PAE mice. Furthermore, a unique spinal circRNA and lncRNA profile, featuring >200 differentially expressed ncRNAs, emerged from morphine-treated PAE mice. Notably, lncRNA and circRNAs with proinflammatory roles, such as circPan3, circRab11, and lncSnhg14, were upregulated, whereas circNr3c2 and circAnkrd12, which are known to exert protective roles against inflammation, were downregulated in PAE mice. Pathways and interaction analysis revealed that these genes are linked to inflammation, cellular stress response, and neuronal-glial interactions that may contribute to pain pathophysiology. Together, these data provide preclinical evidence that PAE and morphine interaction involves spinal proinflammatory activation and are predictive of adverse responses to opioid pain therapy. Dysregulation of ncRNAs may play novel mechanistic roles in neuroimmune dysfunction and allodynic susceptibility under PAE conditions.