Moriche Palm (Aguaje) Extract improves indefinite complaints in Japanese females: a randomized, placebo-controlled, double-blind trial

Background and objective: The fruit of Mauritia flexuosa (moriche palm), which is known as “Aguaje,” has been used for beverages and processed foods. Recently, we found that several methoxyflavans are contained in the fruit and they exhibit estrogenic activities. Therefore, moriche palm extract (MPE) may function as a phytoestrogen and improve the symptoms induced by estrogen deficiency. However, the clinical effects of MPE on females has not yet been reported. We conducted a clinical trial of MPE on undefined complaints related to premenstrual syndrome (PMS) in healthy Japanese females. Methods: This randomized, double-blind, placebo-controlled study examined the effects of MPE (100 mg daily) containing 12.6  g of 5,4'-dihydroxy-7-methoxy-6-methylflavan. Forty-four Japanese women with indefinite complaints in premenstrual and menstrual periods were enrolled in the study. All subjects were randomly allocated into either the MPE (100 mg) group (n=22) or the placebo group (n=22) using a computerized random-number generator. Capsules containing either MPE (100 mg) or placebo were administered for 8 weeks between October and December in 2018. The severity of uncertain complaints and emotional status were evaluated using the Japanese version of the menstrual distress questionnaire (MDQ) as a primary outcome, and Medical Outcomes Study Short-Form 36-Item Health (SF-36) questionnaire at 4 and 8 weeks of ingestion. Blood, urine, and body parameters were also evaluated. Results: Forty-three subjects completed the trial, and the per protocol set comprised 21 subjects in the MPE (100 mg) group and 22 subjects in the placebo group. After ingesting MPE for 4 weeks, arousal in the premenstrual period significantly improved in the MPE (100 mg) group. After 8 weeks, the summary score, water retention, impaired concentration and control during menstrual period significantly improved in the MPE (100 mg) group. Contrarily, among SF-36 domain scores, significant ameliorating effects of MPE were not observed compared with those of the placebo group. Laboratory tests revealed no abnormalities suggesting adverse effects of MPE. Conclusions: MPE (100 mg/day for 8 weeks) improved several indefinite complaint parameters related to mensuration. MPE was suggested to be useful for improving anxiety related to PMS. Keywords: Menstrual distress questionnaire; SF-36 questionnaire; moriche palm; methoxyflavan; indefinite complaint