Metformin suppresses interleukin (IL)-1beta-induced IL-8 production, aromatase activation, and proliferation of endometriotic stromal cells.

Context: Metformin, a widely used treatment for diabetes that improves insulin sensitivity, also has both antiinflammatory properties and a modulatory effect on ovarian steroid production, two actions that have been suggested to be efficacious in therapy for endometriosis.

Objective: To determine whether metformin may be effective for the treatment of endometriosis, we evaluated the effects of this agent on inflammatory response, estradiol production, and proliferation of endometriotic stromal cells (ESCs).

Design: ESCs derived from ovarian endometriomas were cultured with various concentrations of metformin.

Main Outcome Measures: IL-8 production, mRNA expression and aromatase activity, and 5-bromo-2'-deoxyuridine incorporation in ESCs were measured.

Results: Metformin dose-dependently suppressed IL-1beta-induced IL-8 production, cAMP-induced mRNA expression and aromatase activity, and 5-bromo-2'-deoxyuridine incorporation in ESCs.

Conclusion: These results suggest that further investigation into the unique therapeutic potential of metformin as an antiendometriotic drug is warranted.