Brief Summary of Minutes of Annual Meeting

http://soil-physics.nmsu.edu/marbock/W1002/index.html

Keys to prevention of osteoporosis which is one of the leading disabling diseases in the United States are maximizing peak bone mass during growth and minimizing bone loss after menopause. Intake of adequate calcium that can be absorbed and utilized is critical to bone health across the lifespan. Estrogen, which diminishes following menopause is also important Because of both of these issues there is increasing interest in the bioavailability of various fortificants and alternatives to estrogen therapy. Evaluating calcium salts used to fortify foods for bioavailability is important for meeting calcium requirements of persons who do not consume adequate amounts of dairy products which are one of the most bioavailable sources of calcium in the human diet. Results indicate that salts currently being used to fortify cereal and beverage products are absorbed as well as traditional calcium sources. Other research has indicated that rat bone morphology, strength and density are compromised by iron deficiency and exacerbated by calcium restriction. Both iron deficiency and below recommended levels of calcium intake are significant health issues in some segments of the American population. Both are problems in the adolescent population which is of concern since this is the time when most of the bone mass is attained.

There is much interest in antioxidants because of the potential that they decrease the risk of developing some of the leading causes of death in the United States. One antioxidant of interest is B carotene and its ability to yield bioactive retinoids. Results indicate bioavailability of B carotene was 55%. It was also noted that the vitamin A activity of B carotene, even under controlled conditions, was low and variable. Such information is important for researchers who are investigating the effects of B carotene in lowering the risk of developing various conditions like cancer and cardiovascular disease.

Foods with antioxidant properties are also of interest. One is tea, especially green tea. Results from one study indicated that a decoction from green tea was effective in significantly reducing DNA damage in a Caco-2 cell line caused by the oxidizing agent used.

One of the other objectives of this project is the development, refinement and testing of methodologies to assess bioavailability of nutrients and other compounds being tested. An acid extraction protocol coupled to an internally standardized gas chromatography with mass-selective detection was developed to assay total folate in whole blood using common chemicals. In another case, a new sensitive method for measuring bone resorption employing a long-lived isotopic tracer of calcium and accelerator mass spectrometry is being used in post menopausal women to ascertain the efficacy of phytoestrogens in inhibiting bone resorption.

To provide outreach, especially to the scientific community that has limited background and/or resources related to bioavailability research, a website for the W 1002 project is being developed. The initial components of the website can be accessed at http://soil-physics.nmsu.edu/marbock/index.html

Dueker, SR, Lin Y, Jones AD, Mercer R, Fabbro E, Miller JW Green R and Cliford AJ. Determination of blood folate using acid extraction and internaly standardized gas chromatography-mass spectrometry detection. Anal Biochem 2002, 283:266-275.

Hickenbottom SJ, Follett JR, Lin Y, Dueker SR, Burri BJ, Neidlinger TR and Clifford AJ. Variability in conversion of B carotene to vitamin A in mean measured using double-tracer study design. AJCN 2002, 75:900-907.

Lin Y, Dueker SR, Jones AD and Clifford AJ. A parallel processing SPE protocol for the determination of whole blood folate. Anal Biochem 2002, 301:14-20.

Lunetta JM, Zulim RA, Dueker SR, Lin Y, Flaig V, Schneider PD, Wolfe BM and Clifford AJ. Methods for the simultaneous determination of retinol and B carotene concentration in human tissue and plasma. Anal Biochem 2002, 304:100-109.

Hickenbottom SJ, Lemke SE, Dueker SR, Lin Y, Follett JR, Carkeet C, Buchholz BA, Vogel JS and Clifford AJ. Dual isotope test or assessing B carotene cleavage to vitamin A in humans. EJCN 2002, 41:141-147.

Ebeler SE, Brenneman CA, Kim GS, Jewell WT, Webb MR, Chacon-Rodriguez L, MacDonald E, Cramer AC, Levi A, Islas A, Kraus A, Hinrichs SH and Clifford AJ. Dietary catechin and tumor onset in a transgenic mouse model AJCN 2002, 76:865-872.

Mueller HG, Su CL, Dueker SR, Follett JR, Lin Y, Clifford AJ, Buchholz BA and Vogel JS. Semiparmetric modeling of labeled cell kinetics with application to isotope labeling of erythrocytes. Biomet 2002, 58:232-239.

Kway H, Hansen CM, Leklem JE Hardin K and Shultz TD. Improved vitamin B6 status is positively related to lymphocyte proliferation in young women consuming a controlled diet. J Nutr 2002 132:3308-3313.

Medeiros DM, Plattner A, Jennings D and Stoecker B. Bone morphology, strength and density are compromised in iron deficient rats and exacerbated by calcium restriction. J Nutr 2002 132:3135-3141.

Martin BR, Weaver CM, Heaney RP, Packard PT and Smith DL. Calcium absorption rom three salts and CaSO4-fortified bread in premenopausal women. J Ag Food Chem 2002, 50(13):3874-3876.

Weaver CM, Martin BR, Costa, NMB, Saleeb FZ and Huth PJ. Absorption of calcium fumarate salts is equivalent to other calcium salts when measured in the rat model. J Ag Food Chem 2002, 50:4974-4975.

Weaver CM and Liebman M. Biomarkers of bone health appropriate for evaluating functional foods designed to reduce risk of osteoporosis. Br J Nutr 2002, 88(2):S225-S2232.