1. Effects of (-)-epigallocatechin-3-O-gallate on expression of gluconeogenesis-related genes in the mouse duodenum
- Author
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Mamoru Isemura, Noriyuki Miyoshi, Noriko Paeng, Ryuuta Fukutomi, Yoko Ishigami, Takuji Suzuki, Kensuke Yasui, Kyoko Taguchi, Shinjiro Imai, Hiroki Tanabe, and Shingo Goto
- Subjects
medicine.medical_specialty ,Duodenum ,Biology ,complex mixtures ,General Biochemistry, Genetics and Molecular Biology ,Antioxidants ,Catechin ,Mice ,In vivo ,Internal medicine ,Cell Line, Tumor ,Gene expression ,medicine ,Animals ,Humans ,Gene ,Dexamethasone ,Dose-Response Relationship, Drug ,Gluconeogenesis ,food and beverages ,General Medicine ,Molecular biology ,Acetylcysteine ,Hepatocyte nuclear factors ,Dose–response relationship ,Endocrinology ,Gene Expression Regulation ,Cell culture ,Phosphoenolpyruvate carboxykinase ,medicine.drug - Abstract
Green tea has been shown to have many beneficial health effects. We have previously reported that dietary (-)-epigallocatechin-3-O-gallate (EGCG), the major polyphenol in green tea, reduced gene expressions of gluconeogenic enzymes, glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK), in the normal mouse liver. In the present study, we examined the effects of intragastrical administration of EGCG on the expression of gluconeogenesis-related genes in the mouse intestine. The results of experiments with the semi-quantitative reverse transcription-polymerase chain reaction indicated that EGCG at 0.6 mg/head caused a reduced expression of G6Pase, PEPCK, hepatocyte nuclear factor 1α (HNF1α), and HNF4α. Experiments using the quantitative real-time polymerase chain reaction confirmed these effects. We then examined the effects of EGCG using human colon carcinoma Caco-2 cells stimulated with dexamethasone and dibutyryl cAMP. The results were generally consistent with those from the experiments in vivo. The present findings suggest EGCG to contribute to the beneficial effects of green tea on diabetes, obesity, and cancer by modulating gene expression in the intestine.
- Published
- 2011