Spasmogenic activity and acute toxicity of Yumijangquebo, a herbal laxative formulation.

We evaluated the pharmacological properties and spasmogenic activities of Yumijangquebotrade mark, a Korean herbal laxative formulation. Doses in the range 12-50 microg/ml induced a large spasmogenic effect in isolated guinea pig ileum, similar to that induced by acetylcholine. Pre-treating the tissue with atropine (0.2 microM) completely abolished the contractile effect of Yumijangquebo. The spasmogenic effect of Yumijangquebo and the inhibition of this effect by atropine suggest that a cholinergic mechanism is responsible for its effects. Yumijangquebo increased the gastrointestinal motility in ICR mice at doses between 10 and 37 mg/kg. Yumijangquebo exhibited higher activity than three other laxatives tested, which had activities about 85% of that of Yumijangquebo. In an acute toxicity study using Sprague-Dawley rats, the median lethal dose (LD50) of Yumijangquebo was greater than 2000 mg/kg, and we found no pathological changes in macroscopic examination by necropsy of rats treated with Yumijangquebo. We conclude that Yumijangquebo may be safely used as a herbal spasmogenic laxative agent.

Effects of dietary supplements on induction and inhibition of cytochrome P450s protein expression in rats.

Recent surveys show that 18% of adults in the United States use prescription drugs concurrently with herbal or vitamin dietary products. Despite possible dietary supplement-drug interactions through modulation of cytochrome P450s (CYPs), dietary supplements have not been studied at a screening scale to assess their effects on CYPs. In this study, 116 herbal dietary supplements, commercially available for nutrient supply and weight management, were administered to rats to test whether they modulate the expressions of CYP1A2, 2C11, 2D1, 2E1 and 3A1 proteins. Seventy-five percent of the 116 dietary supplements modulated at least one CYP, while 25% had no effect. CYP2C11 protein expression was the most inhibited by supplements (51%), whereas CYP1A2, 2D1, 2E1 and 3A1 were the least inhibited (12-18%). CYP1A2 was the most induced, modulated by 21% supplements, while CYP2E1 and 3A1 were moderately induced (7-8%). CYP2C11 and 2D1 were not induced by any supplement tested in this study. Thus, this study suggests that dietary supplement-drug interactions may occur through modulation of CYPs in humans when they are taken simultaneously.