title: Theflavins and theasinensin A derived from fermented tea have antihyperglycemic and hypotriacylglycerolemic effects in KK-A(y) mice and Sprague-Dawley rats.
abstract: Although tea polyphenols are reported to improve serum glucose and lipid levels by inhibiting amylase activity and reducing lipid absorption, in vivo data are lacking. We evaluated in vivo the antihyperglycemic and hypotriacylglycerolemic effects of theaflavins (TFs) and theasinensin A (TSA) refined from fermented tea to purities of 12 and 59%, respectively. Feeding male KK-A(y) mice diets with 0.1% TFs or TSA for 6 weeks reduced serum glucose levels by >30% compared to a control diet. Rats fed diets containing 0.2% TFs or TSA for 4 weeks had higher fecal fat excretion and 33% lower hepatic triacylglycerol; hepatic fatty acid synthase activity was not affected. Oral administration of TFs or TSA reduced the increase in serum triacylglycerol after an oral bolus of a fat emulsion. These results indicate TFs and TSA induce antihyperglycemic responses in diabetic mice and are hypotriacylglycerolemic in rats by suppressing intestinal fat absorption.
authors.affiliation: Department of Nutrition, University of Nagasaki , 1-1-1 Manabino, Nagayo-cho, Nishisonogi-gun, Nagasaki 851-2195, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Miyata
authors.forename: Shizuka
authors.initials: S
authors.lastname: Tamaru
authors.forename: Takashi
authors.initials: T
authors.lastname: Tanaka
authors.forename: Kei
authors.initials: K
authors.lastname: Tamaya
authors.forename: Toshiro
authors.initials: T
authors.lastname: Matsui
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Nagata
authors.forename: Kazunari
authors.initials: K
authors.lastname: Tanaka
mesh_terms: D000818:Animals; D001578:Benzopyrans / Q000302:isolation & purification / Q000627:therapeutic use*; D044946:Biflavonoids / Q000737:chemistry / Q000302:isolation & purification / Q000627:therapeutic use*; D028241:Camellia sinensis / Q000737:chemistry / Q000382:microbiology; D002392:Catechin / Q000737:chemistry / Q000302:isolation & purification / Q000627:therapeutic use*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000178:diet therapy*; D019587:Dietary Supplements; D031983:Eriobotrya / Q000737:chemistry / Q000382:microbiology; D005285:Fermentation; D005707:Gallic Acid / Q000031:analogs & derivatives; D015228:Hypertriglyceridemia / Q000097:blood / Q000378:metabolism / Q000517:prevention & control*; D007004:Hypoglycemic Agents / Q000302:isolation & purification / Q000627:therapeutic use*; D000960:Hypolipidemic Agents / Q000302:isolation & purification / Q000627:therapeutic use*; D007564:Japan; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010636:Phenols / Q000302:isolation & purification / Q000627:therapeutic use*; D018515:Plant Leaves / Q000737:chemistry / Q000382:microbiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013662:Tea / Q000737:chemistry / Q000382:microbiology; D014280:Triglycerides / Q000097:blood / Q000378:metabolism
chemical_list: D001578:Benzopyrans; D044946:Biflavonoids; D007004:Hypoglycemic Agents; D000960:Hypolipidemic Agents; D010636:Phenols; D013662:Tea; D014280:Triglycerides; C481298:theasinensin A; C056068:theaflavin; D005707:Gallic Acid; D002392:Catechin