FAAH and inflammatory bowel disease: Although AEA levels were found to be increased in UC patients (n = 8) [11], some studies reported an overall reduced AEA signaling in IBD patients, as observed through decreased activity and/or levels of the synthesizing enzyme NAPE-PLD [34,35], as well as through increased activity of the degrading enzyme FAAH [34,35], and through reduced levels of AEA [34].