Iron, absorption/delivery

Increased intestinal absorption capacity for iron (see Intestinal iron absorption ) is an early manifestation of iron deficiency. Absorption of Cd, Pb and Ni are increased in parallel, and this may be a problem in polluted areas (Elsenhans et al. 1991). The risk for low birth weight, preterm delivery and possibly for inferior neonatal health seems to be increased in mothers with marked... 

The mechanism and regulation of intestinal iron absorption remains elusive. A recent intriguing proposal is that integrins on the luminal surface of gut epithelia mediate the safe delivery to a cytosolic acceptor, mobilferrin, with some sequence similarity to the calcium-binding protein calreticulin (Conrad and Umbreit 1993 Conrad et al. 1993). Hereditary hemochromatosis is an inherited disorder in which hyperabsorption leads to iron... 

Goyer and Cherian (1992) measured cadmium, zinc and copper, and metallothionein content of human placentas from 55 uncomplicated, full-term deliveries. The mothers ages ranged from 22 to 39 years, mean 29 years. All were current nonsmokers, but 16 (30%) acknowledged smoking in the past. None were on medication apart from iron and vitamin supplements. For 43 it was the first delivery, for 9 the second, for 1 the third, and for 2 the fourth. Samples of maternal and fetal blood were not obtained. Metals were measured by atomic absorption spectrophotometry and metallothionein by a silver saturation method (Scheuhammer and Cherian 1986). The results are shown in Table 1. Zinc levels of placentas were almost the same as those in the Kuhnert et al. (1988) study, but copper levels were considerably lower. No other comparable measurements of metallothionein were found in the literature. There is a strongly positive correlation between... 

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