Copper and Metabolic Regulation
Copper is of fundamental importance to oxygen utilization and energy metabolism, to growth, in the defense of the organism against oxidation, and in other aspects of normal and defensive body function. The flow of this element and the concentration of specific copper substituents must therefore be regulated according to need. For this purpose, hormones, cytokines, and monokines are released, in response to normal and abnormal conditions, from pregnancy and stress to inflammation and cancer. In relation to these events, ceruloplasmin, the principal copper carrier in the blood plasma, and an acute phase reactant, has been the most studied parameter. Indeed, changes in ceruloplasmin are probably an excellent measure of changes in copper flow among body compartments, as ceruloplasmin is an important source of copper to cells and serves as a scavenger of superoxide for protection against oxidative processes (also involved in infection, inflammation, or tissue damage). These functions, of ceruloplasmin are discussed at length in Chapters 3 and 4. Ceruloplasmin is also very sensitive to dietary status (copper need), of which more will be said in the second half of this chapter, and it may play an important role in copper homeostasis and excretion (Chapter 5). Total serum copper concentrations change in the same direction as ceruloplasmin, because the latter normally accounts for 60% or more of plasma copper (Table 4-12). Other copper components of the plasma have not been as well studied, partly because their significance in terms of quantity and variety has only recently become apparent. Thus, much remains to be learned about changes that may occur in other copper-binding plasma fractions, their regulation, and their significance. With our current state of knowledge, only changes in ceruloplasmin may be adequately described.
KeywordsMetabolic Regulation Copper Deficiency Serum Copper Lysyl Oxidase Copper Status
Unable to display preview. Download preview PDF.