Targeting human Mas-related G protein-coupled receptor X1 to inhibit persistent pain

Significance Chronic pain is a major health and economic problem worldwide with an estimated prevalence reaching epidemic levels of >25% of the population. Most drugs on the market for chronic pain have undesired side effects because their targets exist both inside and outside the pain pathways. Human Mas-related G protein-coupled receptor X1 (MRGPRX1) is a promising target of novel pain inhibitors, mainly because of its restricted expression in primary nociceptive neurons. Our humanized mouse model expressing MRGPRX1 in native nociceptive neurons allowed us to examine physiological roles of MRGPRX1 and to develop therapeutic agents for pain treatment in patients. Our studies suggest that both agonists and positive allosteric modulators of MRGPRX1 may be promising novel drug candidates for managing persistent pain conditions.