Role of 8-iso-prostaglandin F2alpha and 25-hydroxycholesterol in the pathophysiology of endometriosis

Objective: To investigate the involvement of 8-iso-PGF(2alpha) and 25-hydroxycholesterol (25-OH-Chol) in the pathophysiology of endometriosis.

Design: Observational case-control study using enzyme immunoassay and high-performance liquid chromatography (HPLC).

Setting: Postgraduate Institute of Medical Education and Research.

Patient(s): Forty-five women undergoing laparoscopy (n = 25), laparotomy (n = 19), or tubal ligation (n =1).

Intervention(s): Venipuncture and laparoscopic peritoneal fluid (PF) collection.

Main outcome measure(s): The levels of 8-iso-PGF(2alpha) were determined both in urine and PF of all the patients using enzyme immunoassay. The levels of 25-OH-Chol were determined by using reversed phase HPLC both in the plasma and PF samples. Oxidative damage to DNA was assessed by agarose gel electrophoresis.

Result(s): Significantly increased levels of 8-iso-PGF(2alpha) were observed both in urine and PF of women with endometriosis compared with control women. Similarly, higher levels of 25-OH-Chol were observed both in plasma and PF of patients compared with controls and the difference was statistically significant. A clear-cut tailing pattern was observed in DNA of patients with endometriosis, indicating significant DNA damage.

Conclusion(s): Our observations implicate oxidative stress in the pathophysiology of endometriosis. For the first time, we demonstrate that 8-iso-PGF(2alpha) and oxysterols (the known promoters of steroidogenesis) might be the culprits in this disease.