Endometriosis is a Disease of Chronic Inflammation That Cannabis May Treat Very Well
New research has begun, using cannabinoids to stop the progress of endometriosis and treat its symptoms of inflammation and pain.
A leading Israeli research group announced that it will investigate the therapeutic potential of cannabis in endometriosis treatment. Research is significantly lacking in this area.
Endometriosis is a condition in which endometrial cells proliferate and grow in an abnormal fashion. This results the in migration of the tissue outside the uterus. Over the last decade, some have come to suggest that cannabinoids inhibit this abnormal growth. Some believe they restore the balance between cellular growth and cell death, programmed activities of the cell under normal conditions.
Given that the current medical treatments are marginally successful in relieving only some of the symptoms associated in endometriosis (i.e. pain), there is an unmet need for novel, successful therapeutic strategies. The etiology of endometriosis includes inflammation, cell proliferation and cell survival.
The first question arising when considering any treatment is whether the receptors for that substance exist in the target tissue. Fortunately, both CB1 and CB2 receptors (and the enzymes that participate in endocannabinoid turnover) are expressed by many cell types in the human endometrium.
Additionally, the uterus contains a high concentration of anandamide, an endocannabinoid. This tells researchers that cannabinoids from the cannabis plant will also engage with tissues in the uterus.
Cannabinoids as Anti-Inflammatory Agents
Equally important are the studies that have been published describing the role of cannabinoids as anti-inflammatory and anti-proliferative agents. Both of these properties will help treat the symptoms endometriosis.
These studies have also demonstrated that THC has a biphasic effect, a phenomenon that seems to be repeating. At low concentrations (nanomolar range) it has pro-proliferative effect, and at higher concentrations (micromolar range) it has inhibitory effect on cell-proliferation.
Therefore, it is in these higher concentrations that THC would potentially be beneficial in endometriosis. It would inhibit abnormal endometrial cell proliferation. In fact, one study addressed the role of cannabinoids in the proliferation of endometrial cells and showed that treatment with CB1 and CB2 agonist compound both in vitro and in vivo in a mouse model had anti-proliferative effect.
How Cannabis might help Endometriosis
Since endometriosis is a chronic inflammatory disease, it is tempting to speculate that the anti-inflammatory effects of cannabinoids would be highly successful as a therapeutic strategy. Women suffering from endometriosis have elevated levels of circulating cytokines and other inflammatory markers. These constitute a risk for development of autoreactivity (i.e. autoimmune disease).
Immune cells express CB2 in abundance and much less CB1, and it seems that the activation of CB2 receptors is central to the immunosuppressive effects of cannabinoids . This would be beneficial in case of endometriosis. Especially when the inflammation is rampant and out of control.
Granted, under specific conditions cannabinoids can also kick start the immune response, but this seems to be mediated via CB1 receptor activation. Therefore, we need to develop cannabis-based modulators that are CB2 specific.
Research into the potential therapeutic benefit of cannabis-based medicine in endometriosis is only beginning. Since cannabinoids can bind to different cannabinoid receptors. Alternatively, they will bind to non-cannabinoid receptors. Further, they have a dose-dependent effect. Because of these factors, the road to discovery is likely still long. Nevertheless, studies over the past decade have paved the way for future research.