RESUMEN
OBJECTIVES: Mirena® has been shown to improve symptoms in women with minimal to moderate endometriosis. The precise mechanisms for this have not been thoroughly investigated. We investigate here one possible mechanism-alteration in the number of mast cells in the endometriotic tissue. STUDY DESIGN: Tissues (endometrial, endometriotic and normal peritoneal biopsies) prospectively collected from twenty-eight women with laparoscopically confirmed minimal to moderate endometriosis before and 6 months after treatment with Mirena® were processed for immunohistochemistry for ER and PR expression followed by toluidine blue staining for mast cells. Photographs were obtained and the receptors and mast cells identified and quantified. RESULTS: The mean (± SEM) age of the twenty-eight women was 31 (±7.2) (range 18-42) years. Eight of the endometrial biopsies were in the proliferative phase and twenty in the secretory phase. Six months after Mirena®, the number of mast cell expressed in the tissues decreased significantly in the eutopic (P=0.0358) and ectopic endometrium (P=0.0220) but not in the normal peritoneum (P>0.05). There were no ERs or PRs found in mast cells. CONCLUSION: Mirena® causes a reduction in mast cell numbers in ectopic and eutopic endometrium in women undergoing symptomatic treatment of minimal to moderate endometriosis. This reduction could partly explain the efficacy of Mirena® in modulating pain in these women.
Asunto(s)
Anticonceptivos Femeninos/administración & dosificación , Endometriosis/tratamiento farmacológico , Endometriosis/patología , Dispositivos Intrauterinos Medicados , Levonorgestrel/administración & dosificación , Mastocitos/efectos de los fármacos , Adolescente , Adulto , Biopsia , Recuento de Células , Anticonceptivos Femeninos/uso terapéutico , Endometriosis/inmunología , Endometriosis/metabolismo , Endometrio/efectos de los fármacos , Endometrio/inmunología , Endometrio/metabolismo , Endometrio/patología , Femenino , Fase Folicular , Humanos , Levonorgestrel/uso terapéutico , Fase Luteínica , Mastocitos/inmunología , Mastocitos/metabolismo , Mastocitos/patología , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
OBJECTIVES: The levonorgestrel (LNG) intrauterine system (LNG-IUS) has been shown to improve symptoms in women with minimal to moderate endometriosis. The precise mechanism for this is unknown. We hypothesized that this involves alteration in the expression of estrogen receptors (ER) and progesterone receptors (PR). STUDY DESIGN: A prospective study of tissues obtained prospectively from 28 women with laparoscopically confirmed minimal to moderate endometriosis treated with LNG-IUS for 6 months. Endometrial and endometriotic biopsies obtained before and 6 months after treatment were processed and stained for ER-α, ER-ß and PR expression by immunohistochemistry. Photographs were obtained and the receptors quantified. RESULTS: The mean (±SD) age of the 28 women was 31±7.2 (range 18-42) years. Eight of them at initial biopsy were in the proliferative phase and 20 in the secretory phase. ER-α, ER-ß and PR expression decreased significantly in the glandular (P<0.0001) and stromal (P<0.0001) compartments of the eutopic endometrium after treatment with LNG-IUS. Similarly, ER-α, ER-ß and PR were significantly decreased in the stromal compartment of ectopic endometrium (P<0.0001), and significantly decreased in the ectopic glands of ER-α (P<0.0001), ER-ß (P=0.0002) and PR (P=0.0064) expression. CONCLUSION: The ameliorative effect of LNG-IUS on the symptoms of minimal to moderate endometriosis is likely modulated through a decrease in the expression of glandular and stromal ER-α, ER-ß and PR in the ectopic endometrium.