Enteral administration of soybean phosphatidylcholine enhances the lymphatic absorption of lycopene, but reduces that of alpha-tocopherol in rats.
Dietary phosphatidylcholine (PC) increases the lymphatic absorption of triglyceride (TG). This result suggests that dietary PC might also enhance the absorption of other fat-soluble nutrients. We examined the effects of PC on lycopene and alpha-tocopherol absorption in male rats fitted with a thoracic lymph cannula. The lymphatic output was collected after administration of 1 mL of emulsified test oils containing lycopene and/or alpha-tocopherol in 3 separate experiments. The sodium taurocholate-emulsified test oils contained soybean oil (SO; 113 micromol triglyceride), SO containing soybean PC (SPC; 82.5 micromol SO plus 30.5 micromol purified soybean PC) or SO containing egg PC (EPC; 82.5 micromol SO plus 30.5 micromol purified egg PC) with both lycopene and alpha-tocopherol (Expt. 1) or SO, SPC, or EPC with lycopene (Expt. 2) or alpha-tocopherol alone (Expt. 3). In rats administered SPC or EPC, the lymphatic outputs of TG and lycopene were higher, and that of alpha-tocopherol was lower compared with rats administered SO (Expt. 1). The absorption rate for lycopene increased from 0.59% (SO group) to 2.16 and 1.28% in the SPC and EPC groups (P < 0.05), respectively, whereas the corresponding rates for tocopherol were 21.5% for the SO, 14.8% for the SPC, and 12.9% for the EPC groups. The increase in lycopene, but not in triglyceride absorption, was higher in the SPC than in the EPC groups. The promotive effects of SPC and EPC were decreased when lycopene alone was added to the test lipids (Expt. 2), and the inhibitory effects of PC were reduced when alpha-tocopherol alone was added to the test lipids (Expt. 3). Dietary PC increased the lymphatic output of lycopene and TG and decreased that of alpha-tocopherol, suggesting that differences exist between lycopene and alpha-tocopherol in the absorptive mechanisms. The present results also show that the promotive effects of PC on lycopene absorption are influenced by the type of fatty acids in PC.
Nishimukai
Megumi
M
Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Kita-9, Nishi-9, Kita-ku, Sapporo 060-8589, Japan.
Hara
Hiroshi
H
D000818:Animals; D000975:Antioxidants / Q000378:metabolism / Q000493:pharmacokinetics*; D002338:Carotenoids / Q000378:metabolism / Q000493:pharmacokinetics*; D005260:Female; D007263:Infusions, Parenteral; D007408:Intestinal Absorption / Q000187:drug effects; D000077276:Lycopene; D010713:Phosphatidylcholines / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013025:Glycine max; D024505:Tocopherols / Q000378:metabolism / Q000493:pharmacokinetics*
D000975:Antioxidants; D010713:Phosphatidylcholines; D002338:Carotenoids; D024505:Tocopherols; D000077276:Lycopene