![[Feedback]](/icons/banner/feedbackACT.gif){kind=icon}
![[For Subscribers]](/icons/banner/subscriberACT.gif){kind=icon}
![[Archive]](/icons/banner/archiveACT.gif){kind=icon}
![[Search]](/icons/banner/searchACT.gif){kind=icon}
![[Contents]](/icons/banner/tocACT.gif){kind=icon}
|
|
|
|
|
||
-Tocopherol in Adult Rats1
Department of Human Nutrition, Kansas State University, Manhattan, Kansas 66506
2To whom correspondence should be addressed. E-mail: koo{at}humec.ksu.edu
This study was conducted to compare the effects of enterally infused
phosphatidylcholine (PC) and lysophosphatidylcholine (lysoPC) on the
lymphatic absorption of 
-tocopherol (TP) in male rats. In expt.
1, bile-diverted rats with mesenteric lymph cannulas were infused
at 3.0 mL/h for 8 h with a lipid emulsion containing 5.0 µmol
TP, 565 µmol 14C-triolein (14C-OA) and 396
µmol Na+-taurocholate with 80 µmol 1,2-dipalmitoyl PC
(DPPC) or 1,2-dilinoleoyl PC (DLPC) or without PC (NoPC) in 24 mL
phosphate-buffered saline (pH 6.6). In expt. 2, the effects of
1,2-dioleoyl PC (DOPC) and 1-oleoyl-2-hydroxy-PC (lysoPC) on TP and
14C-cholesterol absorption were compared in rats with lymph
cannulas. When DPPC or DLPC was infused, the lymphatic absorption of
TP was lowered drastically. The cumulative absorptions of TP in
rats infused with DPPC and DLPC were 45 and 52%, respectively, of the
control values (NoPC). No significant difference was noted between the
PC groups. In contrast, the absorption of 14C-OA was
increased by 42 to 43% in rats infused with DPPC or DLPC compared with
that in NoPC rats. Phospholipid outputs also were significantly higher
in DPPC (34.0 ± 5.5 µmol/8 h) and DLPC (32.4 ± 2.4
µmol/8 h) rats than in NoPC rats (21.2 ± 4.2 µmol/8 h). When
lysoPC was infused, the absorptions of TP and
14C-cholesterol were increased markedly compared with those
for DOPC, with no significant difference in PL output between groups
infused with DOPC and lysoPC. These observations provide clear evidence
that PC present in a lipid emulsion inhibits TP absorption, whereas
it enhances the absorption of fat. The data also demonstrate that
lysoPC simultaneously increases the absorption of TP and
cholesterol. The findings indicate that luminal PC inhibits the
absorption of TP and that hydrolysis of PC is critical to improving
the intestinal absorption of the vitamin.
KEY WORDS: • absorption • -tocopherol • cholesterol • lysophosphatidylcholine • phosphatidylcholine • rats
This article has been cited by other articles:
|
|
 |
|
  R. S. Bruno, C. E. Dugan, J. A. Smyth, D. A. DiNatale, and S. I. Koo Green Tea Extract Protects Leptin-Deficient, Spontaneously Obese Mice from Hepatic Steatosis and Injury J. Nutr., February 1, 2008; 138(2): 323 - 331. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Wang, S. K. Noh, and S. I. Koo Epigallocatechin Gallate and Caffeine Differentially Inhibit the Intestinal Absorption of Cholesterol and Fat in Ovariectomized Rats J. Nutr., November 1, 2006; 136(11): 2791 - 2796. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. Zou, S. K. Noh, K. Q. Owen, and S. I. Koo Dietary L-Carnitine Enhances the Lymphatic Absorption of Fat and {alpha}-Tocopherol in Ovariectomized Rats J. Nutr., April 1, 2005; 135(4): 753 - 756. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Nishimukai and H. Hara Enteral Administration of Soybean Phosphatidylcholine Enhances the Lymphatic Absorption of Lycopene, but Reduces That of {alpha}-Tocopherol in Rats J. Nutr., August 1, 2004; 134(8): 1862 - 1866. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. B. Loest, S. K. Noh, and S. I. Koo Green Tea Extract Inhibits the Lymphatic Absorption of Cholesterol and {alpha}-Tocopherol in Ovariectomized Rats J. Nutr., June 1, 2002; 132(6): 1282 - 1288. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Sugawara, M. Kushiro, H. Zhang, E. Nara, H. Ono, and A. Nagao Lysophosphatidylcholine Enhances Carotenoid Uptake from Mixed Micelles by Caco-2 Human Intestinal Cells J. Nutr., November 1, 2001; 131(11): 2921 - 2927. [Abstract] [Full Text] [PDF]
|
|
