• Environmental Analysis Health and Toxicology
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• 제19권4호
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• pp.359-366
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• 2004

Iron (Fe) is an essential metal in biological processes, which maintains a homeostasis in the human body. Divalent metal transporter 1 (DMT1) has been known as an iron transporting membrane protein, which is involved in the uptake Fe at the apical portion of intestinal epithelium, and may transport Fe across the membrane of acidified endosome in peripheral tissues. In this study, we studied the tissue distribution of DMT1 in the Fe supplemented (FeS) diet fed rats, and the regulation of DMT1 expression by depleting body Fe. Sprague-Dawley rats were divided into two groups, and fed FeS (120 mg Fe/kg) diet or Fe deficient (FeD, 2∼6 mg Fe/kg) diet for 4 weeks. The evaluation of body Fe status was monitored by measuring sFe, UIBC and tissue Fe concentration. Additionally, DMT1 mRNA levels were analyzed in the peripheral tissues by using the quantitative real time RT-PCR method. In the FeS diet fed rats, the tissue Fe was maintained at a relatively high level, and DMT1 was eventually expressed in all tissues studied. DMT1 was highly expressed in the testis, kidney and spleen, while a moderate levels of DMT1 expression was detected in the brain, liver and heart. In the digestive system, the highest level of DMT1 was found in the duodenum. Feeding the FeD diet caused a reduced body weight gain and depletion of body Fe with finding of decreased sFe, increased UIBC and decreased tissue Fe concentration. The depletion of body Fe upregulated DMT1 expression in the peripheral tissue. The expression of DMT1 was very sensitive to the body Fe depletion in the small intestine, especially in the duodenum, showing dramatically higher levels in the FeD rats than those of the FeS group. In the FeD diet fed animals, the expression of DMT1 was low significantly in other tissues compared with the duodenum. The expression of DMT1, however, was 60∼120% higher in the testis, kidney and spleen, and 30∼50% higher in the lung, liver and heart, compared to the FeS diet fed rats. In summary, DMT1 expression was ubiquitous in mammalian tissue, and the level of expression was the organ-dependent. The expression of DMT1 in peripheral tissues was upregulated by depletion of body Fe. Duodenum was the most sensitive tissue among organs studied during Fe depletion, and expressed the greatest level of DMT1, while other tissues were less higher than in duodenum. This study supports that DMT1 plays a role in maintaining the body Fe level through intestinal uptake as well as homeostasis of Fe in the peripheral tissue.

• Journal of Nutrition and Health
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• 제35권2호
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• pp.223-228
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• 2002

The purpose of this study was to investigate the relationship between iron deficiency without anemia and physical performance in healthy women aged 20-21 yrs. Ten subjects with normal iron stores (serum ferritin $\geq$ 12$\mu\textrm{g}$/L: iron-sufficient group) and 11 subjects with iron depletion without anemia (serum ferritin < 12 $\mu\textrm{g}$/L and serum hemoglobin > 120 g/L: iron-depleted group) were chosen from a group of 50 women and were given physical-performance tests, including determinations of maximum oxygen consumption (VO$_2$ max) and ventilatory threshold. Iron status assessment included determination of hemoglobin, hematocrit, seam ferritin, total iron-binding rapacity, serum iron and transferrin saturation values. Dietary iron intake was assessed based on seven-day food intake records written by the subjects. Physical activity level was estimated by frequency questionnaires and two-week physical activity records were compiled daily by the subjects. Blood ferritin concentration was significantly lower in the iron-depleted group than in the iron-sufficient group (p < 0.05). However, other variables showing iron status was not different between the groups. There were no significant differences in body size, body composition and physical activity levels between the groups. Daily dietary iron, total protein and animal protein intakes of the iron-sufficient group were significantly higher than those of the iron depleted group. However, no differences were found in the amount of dietary vitamin C and fiber between the groups. The values for VO$_2$max and VO$_2$max corrected with weight or fat-free mass were not different between the groups. However, the ventilatory threshold was significantly higher in the iron sufficient group than in the iron-depleted group. The lower ventilatory threshold in the iron-depleted group suggests that iron depletion without anemia could diminish aerobic physical performance in young women. In addition, a significant correlation of physical performance to serum fferritin level was shown only in the iron depleted group.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2005년도 춘계 국제심포지엄 및 학술대회
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• pp.145-145
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• 2005

• 대한지역사회영양학회지
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• 제3권4호
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• pp.556-564
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• 1998

The purpose of this study was to assess the iron nutritional status of college women residing in the Kyungin area. The anthropometric parameters, nutrient intake, and biochemical status of iron were measured for 102 college women. The mean height and weight were 160.3cm and 52.4kg, respectively. The proportion of subjects whose BMI was less than 20 was 41.3%. The proportion of subjects assessed as overweight(25$\geq$25%) assessed by the fat percent(FP) was 53.9%. The mean daily intake of iron was 13.90mg(77.1% of RDA), composed of 0.97mg of heme iron and 12.44mg(69.0% of RDA). When the sources of iron were grouped as rice(including bread), noodle, soup, side dish, and snack, noodle provided, 3.95mg of iron regarded as the highest amount. Subjects were taking 6.72mg(51.4% of RDA) of iron per day from main dishes(rice, bread and noodle). The fifty five percent of the subjects showed iron depletion(serum femitin<20ng/ml)and 33.4% showed suppressed erythropoiesis with iron deficiency(serum ferritin<10ng/ml). The anemic subjects assessed with transferrin saturation (<15%) represented 33.3% of the test population, whereas 11.8% of the subjects possessed less than 12g/dl of hemoglobin. Subjects not satisfied with their body shape were having significantly lower amount of energy intake(p<0.05) than the subjects satisfied with their body shape. College women having mothers who graduated from university had a significantly decreased amount of energy, carbohydrates, fat and vitamin C(p<0.05). The mean RBC and serum iron of the subjects who were on a diet more than one month were lower than those of the subjects who were not on a diet(p<0.05).

• 대한핵의학회지
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• 제10권1호
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• pp.21-34
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• 1976

The diagnosis of iron deficiency rests upon the correct evaluation of body iron stores. Morphological interpretation of blood film and the red cell indices are not reliable and often absent in mild iron deficiency. Serum iron levels and iron-binding capacity are more sensitive indices of iron deficiency, but they are often normal in iron depletion and mild iron deficiency anemia. They are also subject to many variables which may introduce substantial errors and influenced by many pathologic and physiologic states. Examination of the bone marrow aspirate for stainable iron has been regarded as one of the most sensitive and reliable diagnostic method for detecting iron deficiency, but this also has limitations. Thus, there is still need for a more practical, but sensitive and reliable substitute as a screening test of iron deficiency. Pollack et al. (1965) observed that the intestinal absorption of cobalt was raised in iron-deficient rats and Valberg et al. (1969) found that cobalt absorption was elevated in patients with iron deficiency. A direct correlation was demonstrated between the amounts of radioiron and radiocobalt absorbed. Unlike iron, excess cobalt was excreted by the kidney, the percentage of radioactivity in the urine being directly related to the percentage absorbed from the gastrointestinal tract. Recently a test based on the urinary excretion of an oral dose of $^{57}Co$ has been proposed as a method for detecting iron deficiency. To assess the diagnostic value of urinary cobalt excretion test cobaltous chloride labelled with $1{\mu}Ci\;of\;^{58}Co$ was given by mouth and the percentage of the test dose excreted in the urine was measured by a gamma counter. The mean 24 hour urinary cobalt excretion in control subjects with normal iron stores was 6.1% ($1.9{\sim}15.2%$). Cobalt excretion was markedly increased in patients with iron deficiency and excreted more than 29% of the dose. In contrast, patients with anemia due to causes other than iron deficiency excreted less than 27%. Hence, 24 hour urinary cobalt excretion of 27% or less in a patient with anemia suggets that the primary cause of the anemia is not iron deficiency. A value greater than 27% in an anemic subject suggests that the anemia is caused by iron deficiency. The cobalt excretion test is a simple, sensitive and accurate method for the assessment of body iron stores. It may be particularly valuable in the epidemiological studies of iron deficiency and repeated evaluations of the body iron stores.