Carvacrol Shows Potential as a Treatment for Endometriosis with Inflammatory Reaction and Antioxidant Properties, Demonstrated in both In Vivo and In Vitro Studies

Carvacrol is a phenolic monoterpenoid found in essential oils of oregano, thyme, and other plants. It possesses pharmacological activities, including antioxidant, anticancer, and anti-inflammatory properties, against several diseases. However, research on the treatment effect of endometriosis has not yet been conducted. Endometriosis is a condition characterized by tissues resembling the endometrium beyond the confines of the uterus, leading to intense pelvic pain and heightened risks of infertility. This study aimed to confirm the effectiveness of carvacrol as a treatment strategy for endometriosis with inflammatory regulation and antioxidant property. In the in vivo study, C57BL/6 J mice were orally administered 100 mg/kg carvacrol for 4 weeks and confirmed a decreased size of endometriosis lesions in the carvacrol-treated group, increased number of T cells in the spleen, and increased expression of cytokine-related genes in both tissues. Immortalized human ovarian endometriotic stromal cells (ihOESCs), derived from endometriotic lesions in patients, were used as an in vitro model for studying endometriosis pathophysiology. The findings of the in vitro study confirmed that carvacrol regulates calcium homeostasis, induces antioxidant effects, increases inflammatory response, deactivates the phosphatidylinositol 3-kinase (PI3K) signaling pathway, and ultimately induces autophagy. Therefore, we determined that carvacrol is suitable as an anti-inflammatory and anti-oxidant treatment strategy for endometriosis.