[14C]-lycopene and [14C]-labeled polar products are differentially distributed in tissues of F344 rats prefed lycopene.
Epidemiologic evidence suggests a possible role for lycopene-rich foods in the prevention of prostate cancer and cardiovascular disease. Despite active research in disease reduction, there is a paucity of information on the absorption, biodistribution and metabolism of lycopene. The aim of this study was to evaluate the biodistribution of 14C-lycopene (specific activity, 1.83 microCi/mg) and 14C-labeled products after an oral dose of 22 microCi of 14C-lycopene in male rats that had been prefed a lycopene-containing diet (0.25 g lycopene/ kg diet) for 30 d. The percentage of 14C excreted in feces and urine over the 168 h was 68%. Quantitatively, serum 14C levels were maintained between 3 and 24 h then decreased at 72 h (P < 0.05). At all time points the majority of tissue 14C was in the liver (approximately 72%), although total hepatic 14C decreased after 24 h. In a comparison of the extrahepatic tissue at 168 h, the 14C was greatest in adipose tissue followed by spleen and then adrenal; approximately 80% of the 14C in the liver was in the cis and all-trans configuration at all time points. At 3 h, the 14C in seminal vesicles was primarily in the all-trans plus 5-cis forms (70%), but by 168 h, 55% of 14C was present as 14C-polar products. Despite the presence of unlabeled lycopene in the prostate, the primary 14C form was in 14C-polar products (67-92%), even at 3 h. The percentage and amount of 14C-polar products in the dorsolateral prostate lobe increased from 3 to 24 h and then reached a plateau. The data suggest that lycopene may be metabolized differently among tissues in rats prefed lycopene.
Zaripheh
Susan
S
Division of Nutritional Sciences, University of Illinois, Urbana, IL 61801, USA.
Boileau
Thomas W-M
TW
Lila
Mary Ann
MA
Erdman
John W
JW
D000311:Adrenal Glands / Q000378:metabolism; D000818:Animals; D002250:Carbon Radioisotopes; D002338:Carotenoids / Q000097:blood / Q000378:metabolism* / Q000493:pharmacokinetics* / Q000652:urine; D005243:Feces / Q000737:chemistry; D041981:Gastrointestinal Tract / Q000378:metabolism; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D000077276:Lycopene; D008297:Male; D011467:Prostate / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D012669:Seminal Vesicles / Q000378:metabolism; D013237:Stereoisomerism; D013997:Time Factors
D002250:Carbon Radioisotopes; D002338:Carotenoids; D000077276:Lycopene