Effects of the Traditional Japanese Medicine Rikkunshito on Postprandial Glucose and Lipid Metabolism

Abstract

Rikkunshito, a traditional Japanese medicine, has been used as a prokinetic agent to treat functional dyspepsia. Acceleration of gastric emptying of a meal may have a great impact on postprandial blood glucose and insulin responses, possibly resulting in lipid metabolism. The aim of the present study was to investigate associations between blood glucose and insulin levels and GLP-1 response after administration of solid test meals. Effects of Rikkunshito on glucose and lipid metabolism were also evaluated. A meal challenge test (cookie test) was performed on 11 healthy volunteers. Two-week intake of Rikkunshito did not affect postprandial glucose, GLP-1, triglyceride, or RLP-c responses, whereas the plasma insulin level at 60 min was significantly higher after intake of Rikkunshito. FFA levels were also lower from 60 min to 180 min after intake of Rikkunshito. This suggests that GLP-1 does not contribute to enhanced insulin secretion at 60 min after ingestion of solid test meals. It is likely that a prokinetic effect of Rikkunshito could alter insulin secretion after ingestion of solid test meals. Rikkunshito enhances insulin secretion at 60 min after taking solid meals and subsequently reduces plasma FFA levels. These may contribute to preventing metabolic syndrome.