Potential involvement of hemoglobin and heme in the pathogenesis of peritoneal endometriosis.
OBJECTIVE
To test whether hemoglobin may accumulate in the peritoneal cavity in case of endometriosis and to assess whether heme oxygenases (HO), detoxifying heme, are expressed in ectopic endometrium and peritoneal cells.


METHODS
Prospective study involving patients with and without endometriosis.


METHODS
Department of gynecology in a university hospital.


METHODS
Seventy-six patients undergoing laparoscopy for tubal sterilization or infertility and/or pelvic pain.


METHODS
Collection of peritoneal fluid (PF), blood samples, and biopsies from endometrium and peritoneum.


METHODS
Measurement of free hemoglobin and its byproduct, total and direct bilirubin, in serum and PF and analysis of HO-1 and HO-2 expression in biopsies by reverse transcription polymerase chain reaction and semiquantitative immunohistochemistry.


RESULTS
Higher levels of hemoglobin were found in the PF of patients with endometriosis. There was no concomitant increase in bilirubin concentrations in the PF, and HO-1 was poorly expressed in peritoneal mesothelium and macrophages. Heme oxygenase-1 and HO-2 were strongly expressed in ectopic endometrium, especially in red lesions.


CONCLUSIONS
Our results suggest that heme may be involved in the pathogenesis and/or development of endometriosis and that the HO system, although expressed, might be insufficient to detoxify heme in women with endometriosis.
Van Langendonckt
Anne
A
Department of Gynecology, Université Catholique de Louvain, Brussels, Belgium.
Casanas-Roux
Françoise
F
Dolmans
Marie-Madeleine
MM
Donnez
Jacques
J
D000328:Adult; D001202:Ascitic Fluid / Q000737:chemistry; D001663:Bilirubin / Q000097:blood / Q000378:metabolism; D001706:Biopsy; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D004715:Endometriosis / Q000097:blood / Q000209:etiology / Q000378:metabolism*; D005260:Female; D006418:Heme / Q000378:metabolism*; D006419:Heme Oxygenase (Decyclizing) / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D051547:Heme Oxygenase-1; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008565:Membrane Proteins; D010532:Peritoneal Diseases / Q000097:blood / Q000209:etiology / Q000378:metabolism*; D011446:Prospective Studies; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018709:Statistics, Nonparametric
D018076:DNA, Complementary; D006454:Hemoglobins; D008565:Membrane Proteins; D012333:RNA, Messenger; D006418:Heme; C496541:HMOX1 protein, human; D006419:Heme Oxygenase (Decyclizing); D051547:Heme Oxygenase-1; C105245:heme oxygenase-2; D001663:Bilirubin