In the United States, approximately 15% of women of childbearing age have endometriosis. This condition is distinguished by symptoms such as pelvic discomfort, menstrual cramps, and infertility issues. Endometriosis occurs when tissue similar to that which lines the interior of the uterus begins to grow outside it. Such aberrant growth can lead to swelling and bleeding, manifesting in significant pain and other related symptoms.
Dr Sang Jun Han, the study’s corresponding author, is an associate professor of molecular and cellular biology at Baylor College of Medicine and a Center for Reproductive Medicine member. He explains that estrogen heavily influences endometriosis. Estrogen is a hormone crucial for a woman’s reproductive processes but also impacts various other organs, including the heart, blood vessels, bones, breasts, skin, hair, mucous membranes, pelvic muscles, and the brain.
The reliance of endometriosis on estrogen and its inflammatory nature has steered existing treatments towards the elimination of estrogen from the system and the application of anti-inflammatory medications. However, Han points out the limitations of current therapies, noting their low effectiveness, high rate of recurrence, and the adverse impacts they have on other estrogen-sensitive tissues. This challenge has led Han’s research, published in the Journal of Biomedical Science, to seek more effective treatments for endometriosis.
A pivotal aspect of endometriosis is its dependency on estrogen, which acts through estrogen receptors (ERs) ER-alpha and ER-beta on cells, crucial for the condition’s development and advancement. Prior studies, including those conducted by Han’s laboratory, have revealed the significant role of ER-beta in the progression of endometriosis. Dr. Yuri Park, a leading researcher in Han’s team, notes that targeting ER-beta specifically could offer a new therapeutic avenue that avoids the side effects associated with current hormonal treatments focusing on ER-alpha.
In their pursuit of non-hormonal treatments for endometriosis, Han and his team screened natural compounds in a laboratory setting. Their search led to the discovery of oleuropein, a compound found in olive leaves. Oleuropein selectively targets ER-beta without affecting ER-alpha, thereby inhibiting the growth of endometriosis lesions in both mouse and human models.
Remarkably, oleuropein did not exhibit toxicity to the liver, nor did it impede the reproductive capabilities of female mice. In fact, oleuropein administration was found to enhance pregnancy rates in mice affected by endometriosis. These promising results underline the potential of oleuropein as a natural and cost-effective treatment for endometriosis, offering a safer alternative to hormonal therapies. The contributions of Yeon Jean Cho, Nuri Sung, Mi Jin Park, Xiaoming Guan, William E. Gibbons, and Bert W. O’Malley, all affiliated with the Baylor College of Medicine, were also pivotal to this groundbreaking research.
More information: Sang Jun Han et al, Oleuropein suppresses endometriosis progression and improves the fertility of mice with endometriosis, Journal of Biomedical Science. DOI: 10.1186/s12929-022-00883-2
Journal information: Journal of Biomedical Science Provided by Baylor College of Medicine
