Endometriosis is a disorder where tissue that normally lines the endometrium—the mucous membrane lining of the uterus—grows in other places, like the ovaries or Fallopian tubes. When this tissue is shed during a woman’s menstrual cycle, the abnormally growing tissue outside of the uterus is shed as well. Oftentimes, this tissue has nowhere to go and becomes trapped in the body, causing pain that can be extreme enough to lead to hospitalization.
Endometriosis is common: It occurs in about 10–15% of the female population. And yet, not much is known about it—there’s no cure, and pain management options are limited. A number of women have anecdotally reported that cannabis eases the pain associated with endometriosis. Given the lack of treatment options for this condition, exploring these claims and how the endocannabinoid system is involved in this disorder’s pathology could stand to benefit millions of women.
To review, the endocannabinoid system is a network of receptors located throughout the body. Your body makes endocannabinoids, compounds that attach to these receptors. These endocannabinoids are similar in structure to compounds found in cannabis, like tetrahydrocannabinol (THC) and cannabidiol (CBD). This means is that THC and other phytocannabinoids found in marijuana can act on this receptor system to bring about certain therapeutic effects.
A 2016 study in Act Histochemica attempted to look into the endocannabinoid system’s role in endometriosis. According to the study, the uterus contains endocannabinoid receptors CB1 and CB2. Patients with endometriosis have the same amount of receptors as women without the disease. However, patients suffering from endometriosis lack the endocannabinoids to interact with their receptors. It would seem then that an increase in cannabinoids—such as when using cannabis—might help those with endometriosis.
To explore this logic, the researchers first showed that the endometrial cells of patients with the disorder produced fewer endocannabinoids—but they also noticed that these cells proliferated more easily. Interestingly, endocannabinoids are known to assist in apoptosis—a type of programmed cell death. And cannabinoids in general have anti-proliferative actions on some cells, as well as analgesic effects for patients.
Using a cell culture, researchers added compounds that attach to the CB1 and CB2 receptors in the endometrial cells. They found that this led to anti-proliferative and apoptotic effects. What they concluded was that, if you were to add endocannabinoids, which also attach to these receptors, you might be able to get similar outcomes.
These findings could have applications to the endometrial cells that grow outside of the uterus in women who have this disorder. However, this has yet to be studied. Though the development of a cannabis-based medicine to treat endometriosis is being researched and attempted, studies like this lay the groundwork for such goals.
Photo credit: Asdrubal Luna