status report - Office of Dietary Supplements - National Institutes of ...

Publication from this workshop:
• Lamberg, L. (1996) Melatonin potentially useful but safety, efficacy remain uncertain. J. Am.
Med. Assoc. 276(13):1011–1014.
Goal 4: To advance scientific methodology, including epidemiology, in the characterization
of dietary supplements.
ACTIVITIES IN PROGRESS:
Zinc Kinetics in Metallothionein Knockout Mice, A Scientific Study
In conjunction with the National Institute of Diabetes and Digestive and Kidney
Diseases, the ODS is funding a project at Georgetown University, Department of Pediatrics, in
which the investigators are studying the role and action of a key zinc regulatory enzyme,
metallothionein, on the distribution, metabolism, and homeostasis of zinc. This research team
will use kinetic studies with radioactive tracers in knockout animals (animals devoid of the
metallothionein enzyme) to determine zinc absorption and tissue distribution in a mouse model.
This research offers insight into the role of specific gene product(s) on nutrition and metabolism.
Starting date: 1998.
Mechanisms of Antifolate Efficacy in Arthritis, A Scientific Study
The ODS is co-funding a study with the National Institute of Arthritis and
Musculoskeletal and Skin Diseases that is being conducted by researchers at the University of
Alabama at Birmingham. The project examines the interactions between methotrexate treatment
for rheumatoid arthritis and both dietary folic and folinic acid in rats. Results of this study may
help identify one or more biochemical pathways related to folate metabolism that are critical for
the induction of inflammation and tissue injury in arthritis. It could also contribute to the
development of more specific drugs to control arthritis that interfere minimally with the
reduction of dietary folic acid and the recycling of intracellular dihydrofolates. Starting date:
1996.
Publications from this study:
• Baggott, J.E., Morgan, S.L., Sams, W.M. and Linden, J. Urinary adenosine and
aminoimidazolecarboxamide excretion in methotrexate-treated psoriasis patients. (submitted
for publication)
• Baggott, J.E., Morgan, S.L. and Koopman, W.J. (1998) The effect of methotrexate and 7-OH
methotrexate on rat adjuvant arthritis and on urinary aminoimidazole carboxamide excretion.
Arthritis Rheum. 41:1407–1410.
• Morgan, S.L., Baggott, J.E., Lee, J.Y. and Alarcon, G.S. (1998) Folic acid supplementation
prevents deficient blood folate levels and hyperhomocysteinemia during long-term, low dose
methotrexate therapy for rheumatoid arthritis: Implications for cardiovascular disease
prevention. J. Rheumatol. 25: 441–446.
• Morgan, S.L. and Weinsier, R.L., eds. (1998) Fundamentals of clinical nutrition, 2d ed. St.
Louis, MO.: Mosby.
• Tamura, T., Bergman, S.M. and Morgan, S.L. (1998) Hyperhomocysteinemia as a cause of
vascular thrombosis in patients with end-stage-renal disease. Int. J. Artif. Organs 21:72–74.
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