Will latent iron deficiency affect the mitochondrial iron-containing enzymes?

Since information pertinent to the effect of prelatent or latent iron deficiency on tissue iron is scare, the present study was aimed at producing this stage of iron deficiency in rats by phlebotomy and to determine whether the mitochondrial iron-containing enzymes, succinate dehydrogenase (SDH) and glycerophosphate dehydrogenase (GPDH) were affected. These phlebotomized rats showed a subclinical aneamic picture in the blood together with reduced plasma iron and storage iron in the spleen and liver, but an elevated plasma total iron-binding capacity (TIBC). Under this latent iron deficient state, the SHD in the heart and the skeletal muscle with mixed-fibre types (gastrocnemius and plantaris) but not the red (soleus) and white fibres (vastus lateralis) showed reduced activities. No significant changes in GPDH activities were found in these organs. This finding is consistent with our early report (Quisumbing et al., 1985) that even in mild iron deficiency, some loss of mitochondrial functions could have occurred and this could affect the muscular endurance. SDH was more affected by latent iron deficiency than GPDH.