Unravelling the Intricate Link: Mast Cells and Estrogen-Induced Pain Sensitization in Endometriosis

Endometriosis is a prevalent gynaecological disorder characterized by estrogen-dependent lesions. Pain-particularly dysmenorrhea, chronic pelvic pain, and dyspareunia-is the hallmark symptom of endometriosis. While pain mechanisms remain poorly understood, mast cells are now recognized as central mediators of estrogen-induced pain sensitization. Estrogen drives lesion growth and directly activates mast cells within lesions. Upon activation, mast cells release specific mediators, such as histamine and fibroblast growth factor 2 (FGF2), which enhance peripheral pain signalling and drive central sensitization through elevated responsiveness of dorsal horn neurons and increased neurotransmitter release in the spinal dorsal horn. This complex neuroimmune interaction between mast cells and nerve fibres in endometriotic lesions forms a positive feedback loop that amplifies pain. Targeting mast cells and their specific mediators represents a novel therapeutic strategy for pain management, particularly in cases of refractory pain. Further research into mast cell-mediated mechanisms will enable personalized and targeted therapies, revolutionize care and improve the quality of life for patients with endometriosis.