Changes in zinc, copper and selenium status during adjuvant-induced arthritis in rats

Trace elements such as zinc, copper and selenium are involved in the pathogenesis of inflammatory diseases. In order to obtain more information about the overall movements of these minerals during the evolution of an experimental chronic inflammatory process, trace element levels were determined in five body compartments of the rat at several time intervals after induction of adjuvant arthritis. Rapid and significant changes in plasma zinc and copper levels and in liver zinc levels were observed. These modifications occurred as early as those in biochemical parameters of inflammation such as serum fibrinogen and ceruloplasmin, and preceded the appearance of any clinical symptom of the disease. Inverse correlations were found between plasma zinc levels and these two biochemical indices. Other modifications in trace element levels were observed two weeks after disease induction, the most important being a considerable increase in liver copper levels. Although food intake of affected animals decreased with the progression of the disease, there was no evidence of depletion in zinc and copper levels over the study period. A redistribution of body zinc between different biological compartments (mainly plasma and liver) occurred simultaneously with an accumulation of copper in several organs. The decreasing selenium status of animals was not clearly related to the inflammatory process.