Effects of Nelumbo nucifera Leaf Extract on Obesity.

The two main components from a Nelumbo nucifera leaf extract (NnEx) were investigated for their ability to prevent triglyceride accumulation and promoting lipolysis. Sun-dried Nelumbo nucifera leaves were immersed in hot water to extract the soluble components, and the resulting solution was analyzed by LC-MS and nuclear magnetic resonance. The results showed that quercetin-3-O-ß-glucuronide (Q3GA) and quercetin were the key components of the NnEx. In vitro experiments confirmed that quercetin and Q3GA functioned in lipid metabolism by promoting triglyceride degradation through inhibition of the cAMP pathway. In vivo experiments showed that NnEx ingestion inhibited the accumulation of neutral fats in ICR mice and transitioned the hepatocytes of type II diabetic KK-Ay mice out of glycogenosis. These results highlight the ability of NnEx to control metabolism by modulating fat and sugar absorption and may provide an interesting novel treatment for obesity and related lifestyle diseases such as type II diabetes.