Heavy and trace elements are important diagnostic tools during the progression of atherosclerosis; high cholesterol diet supplemented with high zinc level delays or prevents the progression of atherosclerosis

Abstract: The mechanism of atherogenesis has not yet fully understood despite different studies in this area. The effects of high cholesterol diet (HCD) on the changes of trace elements [iron (Fe), copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb)] in several tissues of rabbits have not been well documented before. Thus, the aim of this study was to elucidate the changes in heavy and trace elements in several tissues of rabbits fed on HCD and HCD + Zn for feeding period of 12 weeks compared with the control rabbits; as a diagnostic tool during the progression of atherosclerosis as well as an early detection for cardiovascular diseases and stroke. The HCD group was fed a NOR rabbit chow supplemented with 1.0% cholesterol plus 1.0% olive oil. The HCD + Zn group was fed on NOR Purina Certified Rabbit Chow plus 1.0% cholesterol and 1.0% olive oil supplemented with 350 ppm Zn (total estimate 470 ppm Zn) for the same feeding period of time. Fe, Cu, Zn and Cd concentrations were measured in five types of tissue (kidney, heart, lung, aorta, and liver) from control, HCD and HCD + Zn rabbits using ICP-ES. Comparing HCD to control rabbits, we found an increase in Fe, Cu, Pb and Cd levels in kidney, heart, lung, aorta, and liver tissues of rabbits; while a decrease observed in Zn level in kidney, heart, lung, aorta, and liver tissues. Comparing HCD + Zn with the control rabbits, we found that supplementation of Zn to the HCD decreased the levels of Fe, Cu, Pb, and Cd in kidney, heart, lung, aorta, and liver tissues of rabbits. These results demonstrate that Fe plays a major role during the progression of atherosclerosis through the production of free radicals, deposition and absorption of intracellular and extracellular lipids in the intima, connective tissue formation, and smooth muscle proliferation. Furthermore, inducing anemia in HCD rabbits may delay or inhibit the progression of atherosclerosis. Cu plays a minor role in atherosclerosis. Zn plays a major role in atherosclerosis; it may act as an endogenous protective factor against atherosclerosis perhaps by reducing lesion Fe content