2007 Annual Report 1a.Objectives (from AD-416) Overall, to determine, using animal models, whether copper (Cu) intakes consistent with those observed in humans can adequately support cardiovascular functions. To develop a strategy for assessment of marginal copper deficiency in animals; to use this strategy to determine biomarkers of copper status that are suitable for assessment of marginal status in humans. To determine the contribution of oxygen- and nitrogen-derived reactive species to the cardiomyopathy (metabolic, contractile) induced by Cu deficiency, and the dietary intakes at which this pathology occurs. To determine whether low Cu intakes consistent with those observed in humans can impair nitric oxide-dependent control of blood vessels and blood pressure regulation. To determine whether the oxidative stress induced by Cu deficiency affects homocysteine metabolism and, thereby, cardiovascular function, and whether such effects influence nitric oxide-dependent signal transduction and/or other mechanisms that affect atherosclerosis. To determine whether marginal Zn deficiency can exacerbate or unmask cardiovascular effects of sub-optimal Cu status by virtue of its role in oxidative/nitrosative metabolism. 1b.Approach (from AD-416) Laboratory animals of varying ages and, in some cases, varying genetic makeup will be fed diets containing copper in severely deficient, marginally deficient or adequate amounts for varying periods of time. Based on comparisons to reliable invasive markers of copper status, non-invasive biomarkers will be tested for validity in assessing marginal copper deficiency. Tests of cardiovascular function and examinations of mechanism of depressed function will be made over ranges of copper status varying from severely-deficient to adequate. Cardiovascular functional measurements include heart contractile function, cardiac mitochondrial respiration and respiratory complex activity, blood vessel contractility and blood pressure. Atherosclerosis will be assessed by microscopic observation of blood vessels. Examination of mechanisms of depressed function will focus on the effects of oxidative stress and altered nitric oxide metabolism known to occur in copper deficiency. Such examination will include assessment of oxidative/nitrosative damage, altered nitric oxide signaling and altered homocysteine metabolism and will extend to measurement of transcription factors, mRNA and enzymes that influence and are influenced by oxidative stress and nitric oxide signaling. 3.Progress Report None. 4.Accomplishments Copper supplementation reverses cardiac enlargement caused by pressure overload in mice. In experimental rodents, copper deficiency causes cardiac enlargement that can be reversed by restoring normal copper status. However, little is known about the influence of dietary copper on cardiac enlargement caused by cardiovascular diseases that increase pressure overload. In mice, surgical constriction of the aorta produces chronic pressure overload and eventual cardiac enlargement and failure. It was found that supplementing the mice with about 3 times the normal dietary Cu requirement reversed cardiac enlargement and prevented heart failure in the mice subjected to chronic pressure overload. Copper supplementation improved cardiac enlargement in part by promoting the biogenesis of blood vessels in the heart. IMPACT: Cardiac enlargement and heart failure are a major cause of disability and death in humans. This study suggests that dietary copper requirements may increase in people with certain types of heart disease associated with cardiac enlargement and that supplemental copper may be beneficial for improving cardiac function in these people. [NP 107 Action Plan Component 4: Nutrient Requirements; ARS Strategic Plan Performance Measures 4.1.2: Define functions, bioavailability, interactions, and human requirements (including effects such as genetic, health status, and environmental factors) for known, emerging, and new classes of nutrients in the food supply and provide that information in databases.] Low copper intake during pregnancy but not during lactation results in the reduction of cytochrome c oxidase subunits encoded by both mitochondrial and nuclear DNA in cardiac mitochondria of the offspring. One of our previous studies showed that reduced cardiac cytochrome c oxidase activity produced in the offspring of moderately copper-deficient rats resulted not from low copper intake during lactation, but from low intakes during pregnancy. The present study showed that the reduction in cytochrome oxidase activity resulting from low copper intake during pregnancy was accompanied by reductions in both the mitochondrial- and nuclear-encoded subunits of cytochrome c oxidase in cardiac mitochondria. Furthermore, the reduction in subunit content was not reversed by cross fostering the pups of copper-deficient dams to copper-adequate dams. This indicates that low copper intakes during pregnancy alters the programming of cardiac cytochrome c oxidase expression during fetal development. IMPACT: Dietary surveys indicate that pregnant women often do not meet the current recommended daily intake for dietary Cu. This finding indicates that moderately low Cu intake by pregnant women may alter the programmed development of the fetal heart in a manner that increases the risk of heart disease in their children because of impaired mitochondrial function. [NP 107 Action Plan Component 4: Nutrient Requirements; ARS Strategic Plan Performance Measures 4.1.2: Define functions, bioavailability, interactions, and human requirements (including effects such as genetic, health status, and environmental factors) for known, emerging, and new classes of nutrients in the food supply and provide that information in databases.] 5.Significant Activities that Support Special Target Populations None. 6.Technology Transfer Number of non-peer reviewed presentations and proceedings 5 Number of newspaper articles and other presentations for non-science audiences 1 Review Publications Jiang, Y., Reynolds, C., Xiao, C., Feng, W., Zhou, Z., Rodriguez, W., Tyagi, S., Eaton, J.W., Saari, J.T., Kang, Y.J. 2007. Dietary copper supplementation reverses hypertrophic cardiomyopathy induced by chronic pressure overload in mice. Journal of Experimental Medicine. 204(3):657-666. Nielsen, F.H., Milne, D.B., Klevay, L.M., Gallagher, S., Johnson, L.K. 2007. Dietary magnesium deficiency induces heart rhythm changes, impairs glucose tolerance, and decreases serum cholesterol in post menopausal women. Journal of the American College of Nutrition. 26(2):121-132. Relling, D.P., Esberg, L.B., Johnson, W.T., Murphy, E.J., Carlson, E.C., Lukaski, H.C., Saari, J.T., Ren, J. 2007. Dietary interaction of high fat and marginal copper deficiency on cardiac contractile function. Obesity. 15(5):1242-1257. Saari, J.T., Reeves, P.G., Johnson, W.T., Johnson, L.K. 2006. Pinto beans are a source of highly bioavailable copper. Journal of Nutrition. 136:2999-3004. Saari, J.T., Wold, L.E., Duan, J., Ren, J., Carlson, H.L., Bode, A.M., Lentsch, A.B., Zeng, H., Schuschke, D.A. 2006. Cardiac nitric oxide synthases are elevated in dietary copper deficiency. Journal of Nutritional Biochemistry. doi:10.1016/j.jnutbio.2006.07.006. Uthus, E.O., Reeves, P.G., Saari, J.T. 2007. Copper deficiency decreases plasma homocysteine in rats. Journal of Nutrition. 137:1370-1374. Zeng, H., Saari, J.T., Johnson, W.T. 2007. Copper deficiency decreases complex IV but not complex I, II, III, or V in the mitochondrial respiratory chain in rat heart. Journal of Nutrition. 137:14-18.