Manganese iron deficiency

The distribution of iron-dependent ribonucleotide reductase among other bacteria cannot be assessed at present. Unlike cobalt or manganese, iron deficiency in growth media would lead to various biochemical lesions difficult to distinguish from each other. No other bacterial enzymes have become known that contain non-heme-iron like the E. coli protein. However we shall return to Fe-ribonucleotide reductases in the viral and eukaryotic enzyme systems. 

Adachi, S., Takemoto, K., Hirosuc, T. and Hosogai, Y. (1993). Spontaneous and 2-nitropropane induced levels of 8-hydroxy-2 -deoxyguanosine in liver DNA of rats fed iron-deficient or manganese- and copper-deficient diets. Carcinogenesis 14, 265-268. 

There is a possibility that some milk constituents regulate the absorption of ions in the intestine. In studying manganese metabolism we turned to the low iron content in milk. Iron has received great attention in pediatric nutrition. The concern has been to prevent the anemia caused by iron deficiency earlier often found in childhood. Wide milk consumption by infants and young children makes this food an attractive vehicle for iron fortification. Iron-enriched proprietary milk substitutes can adequately prevent the anemia common to infants who subsist largely on low-iron mother s or cow s milk (53). 

Time Dependence. As the initial iron deficiency (by milk feeding) stimulates iron absorption (53,86-90), which in turn may affect negatively manganese absorption (as described here), the body iron state must also be taken into account. It is therefore useful to establish data about the time factor, i.e. how long the animals can be treated with iron supplemented milk before an alteration in manganese transport is observed and also, how long it takes for manganese transport to return to normal once iron treatment has ceased. 

The fact that the onset of inhibition of manganese transport and retention by iron is faster than its disappearance may also be due to a higher affinity of the carrier binding sites for iron than for manganese. Once filled up with iron these sites will resist iron deficiency for a longer time than they would need to get... 

On the whole, manganese retention in the intestinal wall is far less affected by iron than its transport (47,91), which suggests that the binding sites for manganese (or iron) transport are not the same as for their retention in the mucosa. In other wards, the transport binding sites are more sensitive to iron deficiency. Nothing, of course, can be said about actual molecular differences between the two types of binding sites. 

Under identical experimental conditions iron deficiency defi-nately stimulates much more the transduodenal transport and intestinal uptake of radiomanganese than of radioiron (47,93). This could be explained by the much more stable absorption and other mechanisms in the intestine for iron than for manganese. Whereas the homeostasis of iron is maintained at the level of the intestinal... 

Two conclusions which could have practical importance may be derived so far 1) in combating neonatal iron deficiency, by increasing simultaneously iron and manganese content in milk it might be possible to diminish the risk of manganese deficiency and 2) milk does not seem to be the best means of additional nutrition in exposure to manganese. 

In workers with chronic inhalation exposure, iron deficiency and liver cirrhosis are commonly observed. Chronic inhalation exposure also affects the CNS, resulting in Parkinsonian-like symptoms. Mental aberrations are also observed. The psychiatric disturbance has been called manganese madness . Symptoms include confusion, unusual behavior, and sometimes hallucinations. Apathy, difficulty with speech, and loss of balance are most common. Other symptoms include difficulty with fine motor movement, anxiety, and pain. Manganese intoxication can result in a syndrome of parkinsonism and dystonia. If these extrapyramidal findings are present, they are likely to be irreversible... 

Menstrual losses of blood average 28 milligrams monthly. One in four college-age women are iron deficient, possibly due to ignoring the need for increased iron intake prior to and during menstruation. Diseases that cause iron deficiency are colon cancer, hiatal hernia, ulcers, hemorrhoids, bladder tumor, and diverticulosis. Soft drinks high in phosphates cause iron to be excreted in the urine. Lack of copper or manganese in the diet reduces iron assimilation, as does a deficiency of vitamin C. Oxalic acid foods, such as chard and rhubarb, can block iron intake. 

At normal levels of iron intake, absorption requires uptake from the intestinal lumen by the mucosa and transfer from the mucosa to the portal blood. Both events are inversely affected by the state of body iron stores. In iron deficiency states, nonferrous metals such as cobalt and manganese, which have an ionic radius similar to that of iron and form octahedral complexes with six-coordinate covalent bonds, also are absorbed at an increased rate. Oral administration of a large dose of iron reduces (or temporarily inhibits) the absorption of a second dose of iron by the absorptive enterocytes even in the presence of systemic iron deficiency. The mechanism of mucosal block, which resists acquiring additional iron by the en-teroeytes with high amounts of intracellular iron, is not yet understood. It probably involves set points established in the enterocytes for iron recently consumed in the diet (dietary regulator). 

Chandra SV, Tandon SK. 1973. Enhanced manganese toxicity in iron-deficient rats. Environ Physiol Biochem 3 230-235. 

Mena I, Horiuchi K, Lopez G. 1974. Eactors enhancing entrance of manganese into the brain Iron deficiency and age. J Nucl Med 15 516. 

The micronutrients of major interest to soil chemistry because of plant deficiencies are boron, manganese, iron, cobalt, copper, zinc, and molybdenum. Other ions— chromium, nickel, cadmium, mercury, and lead—behave similarly in soils but the problems are usually plant toxicity. The availability of most of the micronutrient and toxic ions increases with increasing soil acidity. Those present as anions—-molybdenum, chromium, and boron—differ in that their availability generally decreases with increasing acidity. 

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