Opioid Exposure Induces the Expression of the Purinergic Receptor P2RY11 in Human Nociceptors

Abstract

Highlights What are the main findings? Time-series RNA sequencing of human iPSC-derived nociceptors identified P2RY11 as a robust and sustained morphine-inducible transcript. P2RY11/P2Y11 was detected in human dorsal root ganglion neurons, including peripherin- and TRPV1-positive nociceptor populations, and P2Y11 immunoreactivity increased after morphine exposure. What are the implications of the main findings? These findings identify P2RY11/P2Y11 as a previously underappreciated, morphine-responsive target in human nociceptors that may contribute to opioid-driven peripheral plasticity and requires functional testing. Because P2RY11 lacks a mouse/rat ortholog, this work highlights the importance of human-based models for discovering opioid-responsive pain mechanisms not captured by standard rodent systems. Abstract Primary sensory neurons of the dorsal root ganglion (DRG) express mu-type opioid receptors and undergo plasticity that can contribute to both analgesia and maladaptive outcomes such as opioid tolerance and opioid-induced hyperalgesia. Most mechanistic work has relied on rodent models, which may not fully capture the repertoire of opioid-responsive pathways present in humans. In this study, we tested whether morphine exposure reshapes gene expression programs in human nociceptors. Human induced pluripotent stem cell (hiPSC)-derived nociceptors were exposed to morphine (3.5 μM) acutely (1h, 16h) or repeatedly (2–3 days; daily 16h exposure separated by 8h washout) and profiled by time-series RNA sequencing. The transcriptional response to morphine included the induction of a small set of genes across exposure paradigms. P2RY11, encoding the purinergic G protein-coupled receptor P2Y11, was the most robustly induced transcript across the time course, and genes involved in purinergic signaling pathways exhibited coordinated expression dynamics. Since P2RY11 lacks a mouse/rat ortholog, its contribution to nociceptor biology and opioid responses has remained largely underexplored. Using human DRG tissue and primary human DRG cultures from organ donors, we detected P2RY11 mRNA and P2Y11 protein in neuronal populations. We observed increased P2Y11 expression in peripherin-positive neurons after morphine exposure in vitro, corroborating our sequencing results. These findings identify P2RY11/P2Y11 as a morphine-responsive purinergic receptor in DRG neurons and nominate purinergic signaling as a candidate pathway contributing to opioid-driven peripheral plasticity.