Prevention of diet-induced obesity by dietary black tea polyphenols extract in vitro and in vivo.
OBJECTIVE
The effects of certain tea components on the prevention of obesity in humans have recently been reported, although it is still unclear whether black tea consumption is beneficial. We obtained black tea extract (BTPE) consisting of polyphenols specific to black tea, and from it, prepared a polymerized polyphenol fraction (BTP). The effectiveness of oral administration of the BTPE was examined in in vitro and in vivo experiments.


METHODS
Effects of BTPE or BTP on pancreatic lipase activity were investigated in vitro. Male Wistar rats were administered an oral lipid emulsion containing BTPE at a concentration of 500 or 1000 mg/kg body weight and sequential plasma lipid levels were measured. Female C57BL/6N mice were fed a standard or high-fat diet supplemented with 1% or 5% (w/w) BTPE for 8 wk and changes in body weight were examined.


RESULTS
BTP and BTPE inhibited pancreatic lipase activity with an IC(50) of 15.5 and 36.4 μg/mL in vitro, respectively. BTPE suppressed increases in rat plasma triglyceride levels in a dose-dependent manner after oral administration of a lipid emulsion. Furthermore, administration of the 5% BTPE suppressed increases in body weight (P < 0.05), parametrial adipose tissue mass, and liver lipid content (reduced to 56.9% and 81.7% of control mice, respectively, P < 0.05) in mice fed a high-fat diet.


CONCLUSIONS
The BTPE may prevent diet-induced obesity by inhibiting intestinal lipid absorption. It was suggested that the major active component in the BTPE was BTP.
Uchiyama
Satoshi
S
Functional Food Business Project, Kirin Holdings Co, Ltd, Takasaki, Gunma, Japan.
Taniguchi
Yoshimasa
Y
Saka
Akiko
A
Yoshida
Aruto
A
Yajima
Hiroaki
H
D000273:Adipose Tissue / Q000187:drug effects; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D028241:Camellia sinensis / Q000737:chemistry*; D004041:Dietary Fats / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D005260:Female; D005419:Flavonoids / Q000494:pharmacology / Q000627:therapeutic use*; D000960:Hypolipidemic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D020128:Inhibitory Concentration 50; D008049:Lipase / Q000037:antagonists & inhibitors; D050356:Lipid Metabolism / Q000187:drug effects*; D008099:Liver / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009765:Obesity / Q000139:chemically induced / Q000378:metabolism / Q000517:prevention & control*; D009929:Organ Size; D010179:Pancreas / Q000201:enzymology; D010636:Phenols / Q000494:pharmacology / Q000627:therapeutic use*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D059808:Polyphenols; D051381:Rats; D017208:Rats, Wistar; D013662:Tea / Q000737:chemistry; D014280:Triglycerides / Q000097:blood
D004041:Dietary Fats; D005419:Flavonoids; D000960:Hypolipidemic Agents; D010636:Phenols; D010936:Plant Extracts; D059808:Polyphenols; D013662:Tea; D014280:Triglycerides; D008049:Lipase