title: Reproducibility of erythrocyte polyamine measurements and correlation with plasma micronutrients in an antioxidant vitamin intervention study.
abstract: Erythrocyte polyamine measurements have been previously investigated as candidate biomarkers for hyperproliferation and recently as a potential intermediate endpoint in clinical chemoprevention trials with difluoromethylornithine, an inhibitor of polyamine biosynthesis. This study was performed to determine the reproducibility of erythrocyte polyamine measurements and their possible correlation with plasma micronutrients in seven healthy adults in an antioxidant vitamin intervention study. As part of this cross-over intervention study, three subjects took beta-carotene (31.4 mg/day) plus D-alpha-tocopherol acetate (720 IU/day) supplements during the first 3 months and four subjects took the supplements during the second 3 months. Heparinized blood samples were collected at baseline and every month over total 6 months for simultaneous determination of erythrocyte polyamines and plasma micronutrients by the high-performance liquid chromatographic method. For all the measures of erythrocyte polyamines the intraindividual variation was smaller than that between subjects, and three or four measurements required to accurately characterize long-term erythrocyte polyamines for an individual. The intra-class correlations were moderately high for all erythrocyte polyamine measurements, indicating a good reproducibility for intra-individual erythrocyte polyamine measurements. Based on monthly values, significant inverse correlations were found between erythrocyte spermidine and the plasma levels of retinol (r = -0.50) and lutein (r = -0.52). There were also significant inverse associations between erythrocyte spermine and plasma levels of alpha-tocopherol (r = -0.29), lutein (r = -0.44), lycopene (r = -0.29), beta-cryptoxanthin (r = -0.30), and total carotenoids (r = -0.29). The effects of supplementation upon the associations between erythrocyte polyamines and plasma nutrient levels were additionally addressed. The results indicate an acceptable longitudinal reproducibility of erythrocyte polyamine measurements, support the hypothesis that erythrocyte polyamine measurements may be correlated with plasma levels of certain nutrients, and suggest a further biomarker application in cancer prevention trials involving dietary modifications or specific relevant micronutrients.
authors.affiliation: Cancer Etiology Program, Cancer Research Center of Hawaii, University of Hawaii, Honolulu 96813, USA.
authors.forename: W
authors.initials: W
authors.lastname: Wang
authors.forename: O
authors.initials: O
authors.lastname: Kucuk
authors.forename: A A
authors.initials: AA
authors.lastname: Franke
authors.forename: L Q
authors.initials: LQ
authors.lastname: Liu
authors.forename: L J
authors.initials: LJ
authors.lastname: Custer
authors.forename: C M
authors.initials: CM
authors.lastname: Higuchi
mesh_terms: D000328:Adult; D000368:Aged; D000975:Antioxidants / Q000008:administration & dosage*; D001205:Ascorbic Acid / Q000097:blood; D015415:Biomarkers; D002338:Carotenoids / Q000097:blood; D002784:Cholesterol / Q000097:blood; D002851:Chromatography, High Pressure Liquid; D004912:Erythrocytes / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011073:Polyamines / Q000032:analysis*; D012016:Reference Values; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence; D014801:Vitamin A / Q000097:blood; D014810:Vitamin E / Q000008:administration & dosage* / Q000097:blood; D019207:beta Carotene / Q000008:administration & dosage* / Q000097:blood
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D011073:Polyamines; D019207:beta Carotene; D014801:Vitamin A; D014810:Vitamin E; D002338:Carotenoids; D002784:Cholesterol; D001205:Ascorbic Acid