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Published on: July 5, 2017
Black-tea polyphenols decrease micellar solubility of cholesterol in vitro and intestinal absorption of cholesterol
Ikuo Ikeda1, Takashi Yamahira, Masaki Kato
1Laboratory of Food and Biomolecular Science, Department of Food Function and Health, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi 981-8555, Japan. iikeda@biochem.tohoku.ac.jp
Journal of Agricultural and Food Chemistry
|August 5, 2010
Summary
Black-tea polyphenols (BTP) significantly reduce cholesterol absorption in rats by decreasing micellar cholesterol solubility. Specific theaflavins within BTP are key to this cholesterol-lowering effect.
Area of Science:
- Biochemistry
- Nutrition Science
- Pharmacology
Background:
- Dietary cholesterol absorption is a complex process involving micellarization.
- Black-tea polyphenols (BTP) are known for various health benefits, including potential effects on lipid metabolism.
Purpose of the Study:
- To investigate the impact of black-tea polyphenols (BTP) on cholesterol and trioleoylglycerol lymphatic recovery.
- To determine the effect of BTP and its components, theaflavins, on the in vitro micellar solubility of cholesterol.
Main Methods:
- Rats with cannulated thoracic ducts were administered BTP to assess lymphatic recovery of radiolabeled cholesterol and trioleoylglycerol.
- In vitro experiments evaluated the effect of BTP and purified theaflavins on cholesterol solubility in bile salt micelles.
Main Results:
- BTP administration significantly reduced lymphatic recovery of both cholesterol and trioleoylglycerol in rats.
- BTP decreased cholesterol's micellar solubility in a dose-dependent manner.
- Specific theaflavins, including theaflavin-monogallates (TFMGs), TF3G, and TF3'G, effectively removed cholesterol from micelles in vitro, while TF and TFDG did not.
Conclusions:
- The reduction in micellar cholesterol solubility by BTP is a potential mechanism for decreased cholesterol absorption.
- Certain theaflavin compounds are responsible for the observed effect on cholesterol micellar solubility.
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