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.

Hepatic iron status in Malaysians and Singaporeans.

Non-haemoglobin liver iron was estimated in 275 presumably normal individuals from Kuala Lumpur and Singapore at necropsy. Liver Iron concentrations were highest during the first two years after birth but declined sharply during childhood. They then rose gradually and reached a value of 20 mg/100gm in adult males. Liver iron concentrations of childbearing women remained low and it was only after menopause that values in women rose to those of males. Liver iron stores increased with age to a plateau of about 300 mg in adults, suggesting that this value may represent the adult size for liver iron store. Among the three major ethnic groups in Malaysia and Singapore, Chinese, being in a better socio-eonomic class, had larger liver iron stores. The median liver iron concentrations of Malaysians and Singaporeans, on the whole, were lower than those reported from western populations and as many as 35 per cent of the women were in a subclinical state of iron deficiency.