Effects of Hovenia dulcis fruit and peduncle extract on alcohol metabolism.

ETHNOPHARMACOLOGICAL RELEVANCE: The dried fruit and peduncle of Hovenia dulcis Thunberg (Rhamnaceae) (HD) has been used as a folk medicine to treat liver disease, detoxify alcoholism, and prevent and cure hangovers. AIM OF THE STUDY: We investigated the pharmacology of HD on the kinetics of EtOH and on the enzymes related to alcohol metabolism to seek the scientific evidence of HD to prevent hangover, the effectiveness as a folk medicine. MATERIALS AND METHODS: EtOH was orally administered 30 min after oral administration of HD boiling water extract in rats. Then, the profiles of blood EtOH concentrations were measured. Mice were reared with food containing powdered HD for 7 days, and the activities of alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) in liver were measured. Hepa1c1c7 cells were cultured with the medium containing HD extract, and the activities of ADH and ALDH were measured. RESULTS: HD extract reduced the blood EtOH concentrations in rats and induced the activities of ADH and ALDH and mRNA and protein expressions of ADH1B, ALDH1A1, and ALDH2 in the liver of mice and Hepa1c1c7 cells. Dihydromyricetin, one of the ingredients of HD, significantly induced the activities of ADH and ALDH in Hepa1c1c7 cells, however, the fractions containing hydrophilic organic compounds with small molecular weight contributed the most of the activities of HD extract. CONCLUSIONS: We clarified the experimental pharmacological evidences of HD as a folk medicine to detoxify alcoholism and prevent hangovers.

Hypoglycemic Activity and the Mechanisms of Lycium Bark Extract in db/db Mice.

The extract of Lycium bark (LBE), which is the root bark of Lycium chinense, has long been used in China for hypertension, inflammation, and diabetes. LBE has been reported to ameliorate hyperglycemia in mice with alloxan-induced type 1 diabetes, but evidence on the effect of LBE in diabetes had not been enough. Therefore, we investigated the effects of LBE on type 2 diabetes using db/db mice. Nine-week-old male db/db mice were orally administered LBE (425 mg/kg) for 10 weeks. Blood samples were collected under anesthesia for the determination of blood glucose and insulin levels. The blood glucose level was increased in the control group and was unchanged in the LBE group. The blood insulin level was increased in both groups within 4 weeks, but it decreased in the control group and was maintained at a relatively high level in the LBE group thereafter. Furthermore, LBE increased the glucose uptake, which was measured using C2C12 myotubes, in a concentration-dependent manner, independent of the addition of a phosphatidylinositol 3-kinase inhibitor (i.e., LY294002) and an AMP-activated kinase inhibitor (i.e., dorsomorphin). And LBE increased the mRNA expression of glucose transporter (GLUT) 1. These results suggested that LBE decreased the blood glucose level by additive effect such as improvement of the insulin secretion, promoting activity of glucose uptake. These findings suggested that LBE administration can be a novel therapeutic approach for type 2 diabetes.