Sex-Dependent Differences in the Elemental Composition of Internal Organs Determined via Total Reflection X-Ray Fluorescence and Inductively Coupled Plasma Optical Emission Spectroscopy

Abstract

Background: Research on elemental changes in tissues and organs provides valuable information enabling better understanding of the physiological processes occurring in a living organism, as well as the pathogenesis and course of various diseases. They may also contribute to the development of new, more effective, and safer therapeutic strategies. So far, they have been carried out mainly on male individuals because of the easier planning and conducting of experiments as well as the lower variability of the results in comparison with studies involving females. Methods: The significance of incorporating both sexes in research concerning elemental alterations of tissues may be unveiled by data concerning the influence of sex on the physiological levels of selected elements in various rat organs. Therefore, here we determined and compared the levels of P, S, K, Ca, Fe, Cu, Zn, and Se in brains, hearts, kidneys, livers, and spleens taken from male and female rats. To measure the concentrations of the elements in digested tissue samples, ICP-OES and TXRF methods were utilized. Results: Significant differences between male and female rats were found for all the organs examined, and the concentrations of most of the tested elements were higher in males than females. The exception was Fe, the level of which in the kidneys and liver was higher in female rats. Sex influenced the elemental composition of spleen the most. For the brain, heart, kidneys, and liver, differences were sparse and were found mainly for the heavier elements.