Table 1 Summary of endocannabinoid (EC) molecules identified in circulation and tissues of endometriosis (EMS) patients. Most prominent ECs in circulation such as N-arachidonoylethanolamine (AEA), 2-arachidonoylglycerol (2-AG), palmitoylethanolamide (PEA), and oleoylethanolamide (OEA) were found to be altered in circulation. PEA, fatty acid amide hydrolase (FAAH), and N-acylphosphatidylethanolamine phospholipase D (NAPE-PLD) were also found to be altered in the EMS lesions, along with cannabinoid receptors 1 (CB1) and (CB2) 2 and transient receptor potential cation channel subfamily V member 1 (TRPV1)
Area | Endocannabinoid system component | Levels | Significance |
|---|---|---|---|
Systemic | AEA/2-AG (Sanchez et al. 2016) | Elevated | Correlates with pain levels |
PEA/OEA (Sanchez et al. 2016) | Elevated | Â | |
Peritoneal fluid | AEA/2-AGa (Andrieu et al. 2022) | Elevated/reduced | Inflammation |
Follicular fluid | AEA (Fonseca et al. 2021) | Elevated | Inflammation |
Eutopic endometrium | CB1 receptor (Resuehr et al. 2012) | Decreased | Regardless of the cycle phase |
CB1 receptor/CB2 receptor (Shen et al. 2019a) | Decreased | Â | |
TRPV1 (Bohonyi et al. 2017) | Increased | Impact on pain | |
Ectopic lesion | PEA (Lingegowda et al. 2021a) | Increased | Anti-inflammatory |
CB1 receptor/CB2 receptor (Lingegowda et al. 2021a; Bilgic et al. 2017; Shen et al. 2019a) | Decreased | Inflammation | |
FAAH/NAPE-PLD (Bilgic et al. 2017) | Decreased | Higher AEA levels | |
TRPV1/TRPA1 (Bohonyi et al. 2017) | Increased | Increased pain | |
Myometrium | CB1 receptor/CB2 receptor (Shen et al. 2019b) | Increased | Correlates with pain levels |