Daily Coffee Intake Inhibits Pancreatic Beta Cell Damage and Nonalcoholic Steatohepatitis in a Mouse Model of Spontaneous Metabolic Syndrome, Tsumura-Suzuki Obese Diabetic Mice.

BACKGROUND: Metabolic syndrome is one of the most important health issues worldwide. Obesity causes insulin resistance, hyperlipidemia, diabetes, and various diseases throughout the body. The liver phenotype, which is called nonalcoholic steatohepatitis (NASH), frequently progresses to hepatocellular carcinoma. We recently established a new animal model, Tsumura-Suzuki obese diabetic (TSOD) mice, which spontaneously exhibit obesity, diabetes, hyperlipidemia, and NASH with liver nodules. METHODS: We examined the effects of coffee intake on various conditions of the metabolic syndrome using TSOD mice. The daily volume of coffee administered was limited so that it reflected the appropriate quantities consumed in humans. To clarify the effects of the specific components, animals were divided into two coffee-intake groups that included with and without caffeine. RESULTS: Coffee intake did not significantly affect obesity and hyperlipidemia in TSOD mice. In contrast, coffee intake caused various degrees of improvement in the pancreatic beta cell damage and steatohepatitis with liver carcinogenesis. Most of the effects were believed to be caused by a synergistic effect of caffeine with other components such as polyphenols. However, the antifibrotic effects of coffee appeared to be due to the polyphenols rather than the caffeine. CONCLUSIONS: A daily habit of drinking coffee could possibly play a role in the prevention of metabolic syndrome.

Studies on cancer chemoprevention by traditional folk medicines XXV. Inhibitory effect of isoliquiritigenin on azoxymethane-induced murine colon aberrant crypt focus formation and carcinogenesis.

Isoliquiritigenin is a natural pigment with the simple chalcone structure, 4,2',4'-trihydroxychalcone. The effect of this compound on azoxymethane (AOM)-induced colonic aberrant crypt focus and tumor formation in ddY mice was examined. Administration of 15 ppm of isoliquiritigenin in drinking water, significantly suppressed AOM-induced aberrant crypt focus formation (p<0.01), with an inhibitory ratio of 37.3%. Isoliquiritigenin also inhibited AOM-induced colon carcinogenesis by administration in a mixed diet. The average number of tumors was 14.6+/-8.9 items in the control group and were 7.3+/-7.3, 3.9+/-5.6, 4.7+/-6.5 items in the 10, 100 and 250 ppm in the isoliquiritigenin treated groups, respectively. In histopathological studies, the tumors were identified as adenoma and adenocarcinoma, however, significant differences were not observed between the control group and isoliquiritigenin treated groups. These results indicated that isoliquiritigenin might be a potential chemopreventive agent against colon cancer.