Full Length Research Paper

The changes of iron and zinc concentrations in heart and aortic tissues of rabbits fed on high fat diet during the progression of atherosclerosis

Mohamed Anwar K. Abdelhalim

Department of Physics and Astronomy, College of Science, King Saud University, P. O. Box 2455, Riyadh-11451, Saudi Arabia. E-mail: abdelhalimmak@yahoo.com, mabdulhleem@ksu.edu.sa.

Accepted 22 July, 2010

Abstract

High level of serum triacylglycerol and cholesterol is an important risk factor for the progression of atherosclerosis. The severity of atherosclerosis can be markedly influenced by iron (Fe) and zinc (Zn) overload or deficiency in aorta tissues of the rabbits. The changes of Fe and Zn in heart and aortic tissues of rabbits during the progression of atherosclerosis have not been well documented. Thus, the aim of the present study was to evaluate the changes of Fe and Zn in heart and aortic tissues of rabbits fed on high fat diet (HFD) for 12 weeks. The HFD group was fed a normal rabbit chow supplemented with 1.0% cholesterol plus 1.0% olive oil for a feeding period of 12 weeks. Fe and Zn concentrations were measured in two types of tissue from control and HFD rabbits using atomic absorption spectroscopy (AAS). The Fe concentration was significantly (p < 0.05) increased in HFD rabbits (Mean ± SE; heart: 10.52 ± 1.04 and aorta: 3.01 ± 2.61; n = 25 specimens) compared with control rabbits (Mean ± SE; heart: 8.41 ± 0.01 and aorta: 2.25 ± 0.37; n = 20 specimens). The Fe concentration was increased with percentage normalized changes of 25.09% in heart and 33.78% in aortic tissues of HFD rabbits compared with control rabbits while the Zn concentration was significantly (p < 0.05) decreased with percentage normalized changes of 14.39% in heart and 18.37% in aortic tissues of HFD rabbits compared with control rabbits. AAS was used to elucidate the changes of Fe and Zn in heart and aortic tissues of HFD rabbits compared with control rabbits. The findings of this study can be summarized as follows; percentage normalized change of increase of Fe was 25.09% in heart tissue accompanied by percentage normalized change of decrease of Zn 14.39% in heart tissue while percentage normalized change of increase of Fe was 33.78% in heart tissue accompanied by percentage normalized change of decrease of Zn 18.37% in aortic tissue. This study suggests that the increase in Fe concentrations in heart and aortic tissues may accelerate atherosclerosis through the production of free radicals while the decrease in Zn concentrations may act as a protective factor against atherosclerosis perhaps by reducing lesion Fe content. These results suggest that the changes in Fe and Zn concentrations in heart and aortic tissues of rabbits are closely related to the progression of atherosclerosis.

Key words: High cholesterol diet, iron, zinc, atherosclerosis, heart and aortic tissues, atomic absorption spectroscopy.