Identifying the effects of royal jelly on intestinal motility

In this study, Japanese researchers investigated the effects of royal jelly on the motility of mouse ileum both in vitro and in vivo. They reported their findings in an article published in the Journal of Medicinal Food.

• Royal jelly is widely used in cosmetics and as a dietary supplement to relieve various ailments, such as dry skin, fatigue, menopause and constipation.
• However, the mechanisms underlying its effect on intestinal motility and whether it does improve constipation remain unclear.
• Using myograph methods, the researchers found that royal jelly dose-dependently induced contractions in segments of isolated mice ilea. These contractions were inhibited by treatment with atropine.
• On the other hand, treatment with the cholinesterase inhibitor, eserine sulfate, enhanced royal-jelly induced contractions. Acetylcholinesterase treatment together with royal jelly did not induce ileum contraction.
• Meanwhile, the nitric oxide synthase inhibitor N^G-nitro-l-arginine methyl ester did not affect royal jelly-induced contractions but enhanced nicotine-induced contractions significantly.
• In contrast, administration of 300?mg/kg royal jelly did not influence gastrointestinal (GI) transit in normal mice as well mice with loperamide-induced constipation.

Based on these findings, the researchers concluded that acetylcholine in royal jelly acts on the muscarinic receptors of mouse intestinal smooth muscle, making it contract. However, single oral administration of royal jelly is not enough to improve constipation in vivo, suggesting that it is a gentle laxative.

Journal Reference:

Miyauchi-Wakuda S, Kagota S, Maruyama-Fumoto K, Wakuda H, Yamada S, Shinozuka K. EFFECT OF ROYAL JELLY ON MOUSE ISOLATED ILEUM AND GASTROINTESTINAL MOTILITY. Journal of Medicinal Food. 06 August 2019;22(8):789–796. DOI: 10.1089/jmf.2018.4340