EFFECT OF DIFFERENT DEGREES OF MODERATE IRON-DEFICIENCY ON THE ACTIVITIES OF TRICARBOXYLIC-ACID CYCLE ENZYMES, AND THE CYTOCHROME-OXIDASE, AND THE IRON, COPPER, AND ZINC CONCENTRATIONS IN RAT-TISSUES

Severe iron deficiency results in complex systemic disorders e.g., inc luding metabolism of energy and minerals. To investigate whether also moderate iron depletion may alter the activities of citric cycle enzym es and the cytochrome oxidase, the trace element status, and serum enz ymes indicative of cell damage, this experiment was carried out with r ats supplied with sub-optimal iron (9, 13 and 18 mg iron per kg diet) over a total of 5 weeks. The study included 3 pair-fed groups and an a d libitum group, fed with 50 mg iron/kg diet. All iron-restricted rats were classified as iron-deficient on the basis of reduced iron concen trations in body and iron-depending blood parameters. Body weight gain and catalase activity in kidney were lowered in rats receiving the lo west dietary iron level, exclusively. Rats fed 9 and 13 mg iron per kg diet had nearly 6- and 3-fold, respectively higher platelet counts in blood than their corresponding pair-fed controls. The activities of t ransaminases ASAT and ALAT, alkaline phosphatase, glutamate dehydrogen ase and lactate dehydrogenase in serum which are indicative of cell da mage were also markedly influenced by moderate dietary iron restrictio n, in which the enzyme levels in serum increased with intensifying iro n depletion. Although, moderate iron restriction to young male rats wa s associated with marked alterations in iron status and serum enzymes, the activities of tricarboxylic acid cycle enzymes including malic de hydrogenase, fumarase, and isocitric dehydrogenase as well as cytochro me oxidase in liver remained largely unaffected. Only hepatic aconitas e showed a somewhat reduction with iron depletion. Moreover, iron rest riction was also accompanied with an accumulation of copper in liver w hich was significant for rats fed 9 and 13 mg iron per kg diet, wherea s zinc status remained completely unaffected by moderate iron deficien cy. It can be concluded, that a short-term moderate iron deficiency wi th ranging hemoglobin concentrations from 66 and 121 g/L, was accompan ied with altered platelet counts, serum enzyme activities indicative o f cell damage, and hepatic copper concentrations, but the activities o f the tricarboxylic acid cycle enzymes and cytochrome oxidase in liver remained largely unaffected.