ABSTRACT
Manganese is an essential trace element because of its role in a number of enzyme systems and perhaps, because of its role as an intracellular metabolic regulator. The involvement of manganese in enzyme systems can be differentiated between manganese-containing enzymes and manganese-activated enzymes. Absorption of manganese is influenced most notably by iron; these two elements may utilize a common absorptive pathway. Manganese enters the portal system bound to a ligand, and recent findings indicate that the ligand may be albumin,6 although other findings suggest transferrin. Primary problems encountered in manganese-deficient animals include skeletal abnormalities. The primary causative factor apparently is decreased glycosyltransferase activity that leads to a subsequent decrease in proteoglycan formation. An initial indication of this relationship came from the report of an insulin-resistant man whose blood glucose was lowered by administration of oral manganese supplements. The interaction between iron and manganese has been noted in numerous studies and reviewed extensively.
