Intestinal alkaline phosphatase: the molecular link between rosacea and gastrointestinal disease?

Rosacea is a common inflammatory condition of the facial skin of unknown etiology, which frequently occurs in combination with gastrointestinal disorders. Many dietary and hormonal factors are known to affect the severity of rosacea symptoms, several of which also modulate the activity of the enzyme intestinal alkaline phosphatase (IAP). The role of IAP in inhibiting an inflammatory response to intestinal bacteria suggests a mechanism by which intestinal pathologies may be linked to the skin inflammation characteristic of rosacea. Analysis of alkaline phosphatase activity is routinely performed on blood samples, and methods to quantify enzyme activity of the intestinal isoform specifically have been described. Correlations between IAP activity and rosacea symptoms in patients and controls can thus be screened by noninvasive and inexpensive means. If IAP activity is found to be low in rosacea patients, acute symptoms could be treated with oral IAP supplementation, and trials of IAP-activating medications currently used in gastrointestinal disease could be initiated in rosacea patients. More importantly, the safe and long-term control of rosacea could be undertaken by patients themselves through dietary modification to naturally increase IAP activity.