|DALLE LUCCA, J|
Submitted to: American Society for Experimental Biology and Medicine Proceedings
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/14/2002
Publication Date: 7/1/2002
Citation: Dalle, L.J.J., Saari, J.T., Schuschke, D.A. 2002. Neointima formation in the rat carotid artery is exacerbated by dietary copper deficiency. Proceedings of the Society for Experimental Biology and Medicine. 222:487-491.
Interpretive Summary: Prior studies have indicated that structure and function of blood vessels are altered in dietary copper deficiency. In particular the blood vessel response to inflammatory stimuli is known to be enhanced in copper deficiency. The purpose of this study was to determine how the blood vessel responds to injury. Blood vessels in copper-adequate and copper-deficient rats were injured by distending them with an inflated balloon. Two weeks following this injury, microscopic examination of the blood vessels of copper-adequate rats revealed that the repair process had thickened the vessel walls, but in copper-deficient rats, this repair process had been enhanced to such a degree that the vessels were almost totally blocked. This finding provides further support for the view that the inflammatory response to injury is exaggerated by copper deficiency in rats. Further, because balloon inflation of blood vessels is a common mode of treatment for atherosclerotic blood vessels, the findings suggest that proper copper nutrition would improve the results of such treatment. Such information will help scientists and consumers understand the importance of adequate copper nutrition in cardiovascular function.
Technical Abstract: Dietary copper is an essential trace element with roles in both functional and structural aspects of the cardiovascular system. In particular the vascular response to inflammatory stimuli is known to be significantly augmented in copper-deficient rats. The current study was designed to quantify the extent of injury-induced neointimal proliferation and restenosis in rats fed diets either adequate or deficient in copper. Male, weanling Sprague-Dawley rats were fed purified diets that were either adequate (CuA; 5.6 ug/g) or deficient (CuD; 0.3 ug/g) in copper for 4 weeks. Histomorphometric analysis of cross sections from carotid arteries showed increased neointimal formation in the CuD group compared to the CuA controls (neointima/media ratio: 1.75 +/- 0.57 vs 0.69 +/- 0.21 respectively). These results correspond with data indicating that the activity of Cu/Zn-SOD is depressed in rats fed this CuD diet. Since superoxide anion and redox status are known to play a key role in the extent of neointimal formation in response to injury, we propose that the exaggerated neointimal proliferation seen in the CuD group is the result of the diminished Cu/Zn-SOD activity.