Targeting P2X receptor signaling for chronic visceral pain and beyond.

P2X receptors (P2XRs) are ATP-gated cation channels that play a pivotal role in chronic visceral pain (CVP). This review highlights the central contribution of the ATP-P2X3/4/7 axis in peripheral and central sensitization underlying CVP. Recent discoveries have identified the non-coding RNA miR-1306-3p as an endogenous nanomolar agonist of P2X3 receptors, coupling chronic stress to visceral pain via an epigenetic pathway. Moreover, persistent DNA methylation changes at the P2RX7 locus in spinal astrocytes create a "pain memory" that limits the durability of conventional antagonists. The first-generation P2X3/P2X7 antagonists (e.g., AF-219, AZD-9056, NC-2600) failed in clinical trials, primarily due to species-specific receptor pharmacology, the lack of ATP-based biomarkers for patient stratification, and irreversible central sensitization driven by epigenetic marks. To overcome these hurdles, we propose a precision-medicine framework that includes: (1) CRISPR-dCas9-based epigenome editing as a potential one-time "pain-memory eraser"; (2) patient stratification using sweat-ATP levels; and (3) human iPSC-derived neuron screening to improve translational predictability. This integrated approach holds promise not only for CVP related to irritable bowel syndrome (IBS), but also for other pain conditions.