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1.
Sulfite is a potentially toxic molecule that might enter the body via ingestion, inhalation, or injection. For cellular detoxification, mammalians rely on sulfite oxidase to convert sulfite to sulfate. The purpose of this research was to determine the effect of sulfite on zinc, iron, and copper levels in rat liver and kidney tissues. Forty normal and sulfite oxidase-deficient male albino rats were divided into four groups that included untreated controls (group C), a sulfite-supplemented group that received 70 mg sodium metabisulfite per kilogram per day (group S), a sulfite oxidase-deficient group (group D), and a sulfite oxidase-deficient group that was also given 70 mg sodium metabisulfite per kilogram per day (group DS). The iron and zinc levels in the liver and kidney in groups S and DS were not affected by sulfite treatment compared to their respective controls (groups C and D). Sulfite exposure led to an increase of kidney copper content in the S group when compared to untreated controls. The kidney copper levels were significantly increased in the unexposed deficient rats, but it was not different than that of the deficient rats that were given oral sulfite treatment. These results suggest that kidney copper levels might be affected by exogenous or endogenous sulfite. An erratum to this article is available at .  相似文献   

2.
The interaction between dietary copper and zinc as determined by tissue concentrations of trace elements was investigated in male Sprague-Dawley rats. Animals were fed diets in a factorial design with two levels of copper (0.5, 5 μg/g) and five levels of zinc (1, 4.5, 10, 100, 1000 μg/g) for 42 d. In rats fed the low copper diet, as dietary zinc concentration increased, the level of copper decreased in brain, testis, spleen, heart, liver, and intestine. There was no significant effect of dietary copper on tissue zinc levels. In the zinc-deficient groups, the level of iron was higher in most tissues than in tissues from controls (5 μg Cu, 100 μg Zn/g diet). In the copper-deficient groups, iron concentration was higher than control values only in the liver. These data show that dietary zinc affected tissue copper levels primarily when dietary copper was deficient, that dietary copper had no effect on tissue zinc, and that both zinc deficiency and copper deficiency affected tissue iron levels.  相似文献   

3.
X-ray fluorescence and atomic absorption spectrometry were used to measure the concentrations of zinc, copper, and magnesium in the heart, liver, skeletal muscle, and kidney following isoproterenol-induced myocardial necrosis in male albino rats. Serum activities of lactic dehydrogenase (LDH), creatine phosphokinase (CPK), and glutamic oxaloacetic transaminase (SGOT) were also measured. There was depletion of myocardial zinc, copper, and magnesium on d 1, followed by an uptake of all these elements on d 2. The liver showed a significant uptake of magnesium, along with depletion of copper. There was no change in the kidney and skeletal muscle concentrations of these elements. Possible explanations for the observed changes and their therapeutic significance are presented.  相似文献   

4.
Manganese is an essential dietary nutrient and trace element with important roles in mammalian development, metabolism, and antioxidant defense. In healthy individuals, gastrointestinal absorption and hepatobiliary excretion are tightly regulated to maintain systemic manganese concentrations at physiologic levels. Interactions of manganese with other essential metals following high dose ingestion are incompletely understood. We previously reported that gavage manganese exposure in rats resulted in higher tissue manganese concentrations when compared with equivalent dietary or drinking water manganese exposures. In this study, we performed follow-up evaluations to determine whether oral manganese exposure perturbs iron, copper, or zinc tissue concentrations. Rats were exposed to a control diet with 10 ppm manganese or dietary, drinking water, or gavage exposure to approximately 11.1?mg manganese/kg body weight/day for 7 or 61 exposure days. While manganese exposure affected levels of all metals, particularly in the frontal cortex and liver, copper levels were most prominently affected. This result suggests an under-appreciated effect of manganese exposure on copper homeostasis which may contribute to our understanding of the pathophysiology of manganese toxicity.  相似文献   

5.
To clarify the changes of mineral levels in different tissues of riboflavin-deficient rats, Wistar rats were separated into three groups. One group was fed a diet ad libitum that was deficient in riboflavin. The other two were fed either the complete diet that was weight-matched to the riboflavin-deficient group or fed a complete diet ad libitum. In riboflavin-deficient rats, the hemoglobin concentration and riboflavin contents of blood, liver, and kidney were significantly decreased, compared with weight-matched and ad libitum-fed controls. The mineral concentrations of tissues are summarized as follows: The iron (Fe) concentration in the heart, liver, and spleen was decreased in the riboflavin-deficient group compared with the other groups. Calcium (Ca) and magnesium (Mg) concentrations in tibia were decreased in the riboflavin-deficient group compared with the other two groups. Copper (Cu) concentration was increased in the heart and liver when the riboflavin-deficient group was compared with the other groups. Zinc (Zn) concentration was increased in tibia when the riboflavin-deficient group was compared with the other groups.  相似文献   

6.
An enormous amount of data has been published in recent years demonstrating melatonin's defensive role against toxic free radicals. In the present study, we examined the role of melatonin as an antioxidant against the effect of continuous light exposure. Rats were divided into three groups. Control rats (group A) were kept under natural conditions whereas other group of rats (group B and C) were exposed to constant light for inhibition of melatonin secretion by the pineal gland. Group C rats also received melatonin via s.c. injection (1 mg x kg(- 1) body weight x day(- 1)). At the end of experiment, all animals were sacrificied by decapitation, serum and tissue samples were removed for determination of malondialdehyde (MDA), a product of lipid peroxidation, conjugated dienes levels and glutathione peroxidase (GSH-Px) activity levels. It was found that lipid peroxidation was increased in the rats which were exposed to constant light. Melatonin injection caused a decrease in lipid peroxidation, especially in the brain. In addition, melatonin application resulted in increased GSH-Px activity, which has an antioxidant effect. Thus, melatonin is not only a direct scavenger of toxic radicals, but also stimulates the antioxidative enzyme GSH-Px activity to detoxify hydroxyl radical produced by constant light exposure.  相似文献   

7.
To evaluate the species specificity of Cd accumulation and the relationship of Cd with other essential metals and metallothionein (MT), the concentrations of Cd, Zn, Cu, and Fe in the liver and kidney and the MT concentrations in the soluble fractions of the liver and kidney were determined in Cd-uncontaminated nonhuman primates (11 species, 26 individuals) kept in a zoo and two wild-caught Japanese macaques. The compositions of metal-binding proteins in the soluble fractions were also investigated by high-performance liquid chromatography (HPLC). The hepatic Cd concentration was 0.03–14.0 μg/g and the renal Cd concentration was 0.35–99.0 μg/g, both varying greatly and being higher in nonhuman primates, which were more closely related to man. The hepatic Zn concentration was 24.0–176 μg/g and the renal Zn concentration was 13.5–138 μg/g, showing 7- to 10-fold differences, and a correlation (r=0.558, p<0.01) was found between renal Zn and renal Cd concentrations. It was proved that in the liver, MT is more closely correlated with Zn (r=0.795, p<0.001) than with Cd (r=0.492, p<0.01) and that in the kidney MT is correlated with both Cd (r=0.784, p<0.001) and Zn (r=0.742, p<0.001). HPLC analysis of metals bound to MT-like protein in chimpanzees, de Brazza’s monkeys, and Bolivian squirrel monkeys showed that more than 90% of Cd in both the liver and kidney, approx 40% of Zn in liver and 28–69% of Zn in kidney were bound to MT-like protein. The higher percentage Zn was bound to high-molecular protein.  相似文献   

8.
Information about the health risks or the subtle adverse health effects that might be associated with low-level lead exposure on micronutrient metabolism are scarce in the literature. The present work investigated the subtle adverse health effects of exposure to progressively low levels of lead on the metabolism of two micronutrients, copper and zinc in different tissues of the rat. Rats were exposed to 200, 300 and 400 ppm lead in their drinking water for 12 weeks. Lead, copper and zinc concentrations were determined in blood, liver, kidney, heart, spleen and brain of the animals. While the imbalance in zinc metabolism was characterized by a deposition of zinc in the kidney and to a lesser extent in the heart of the animals, imbalance in copper metabolism was characterized by a depletion of blood and splenic copper concentrations as well as renal and cardiac accumulation of copper. Hepatic and brain copper and zinc contents, together with blood zinc were not affected by the 12-week lead exposure. A linear relationship was observed between lead dose and lead accumulation in the spleen, whereas a non-linear relationship was observed between lead dose and lead accumulation in blood, liver, kidney and heart. Our findings indicate that exposure to progressively low-level lead concentrations results in imbalance in copper and zinc in the organism and this might be a factor in propensity toward behavioral disorders observed in lead exposure.  相似文献   

9.
10.
The effect of long-term dietary cadmium treatment upon the distribution of the metals copper, iron and zinc has been compared in various organs of male and female rats. The renal accumulation of cadmium was similar in both sexes without a plateau being reached. In contrast, the hepatic accumulation of cadmium was higher in the female than in the male rat and a plateau was observed after 30–35 weeks of dietary cadmium treatment. Most of the cadmium which accumulated in these organs was recovered in the metallothionein fraction and the concentration of hepatic cadmiumthionein in the female rat was correspondingly higher than in the male rat. Accumulation of cadmium was associated with an increased zinc concentration in the liver and an increased copper concentration in the kidney; these increases were correlated with increases in liver and kidney metallothioneins induced by cadmium. Uptake of cadmium into organs other than liver and kidney occurred to a small extent but was not associated with changes in the concentration of copper and zinc. Cadmium also accumulated in the intestinal mucosa where it could be recovered in a fraction corresponding to metallothionein. A loss of iron from the liver and kidney was also observed following dietary cadmium treatment and involved mainly a loss of iron from ferritin.  相似文献   

11.
Dietary chitosans with different molecular weight Mw and the degree of deacetylation DDA (high molecular weight chitosan HCS with Mw 7.60 × 105 and DDA 85.5%, middle molecular weight chitosan MCS with Mw 3.27 × 104 and DDA 85.2%, chito-oligomer COS with Mw 0.99 × 103 and DDA 85.7% and water-soluble chitosan WSC with Mw 3.91 × 104 and DDA 52.6%) were used at the 1.05% level to feed mice for 90 days. Afterwards no pathological symptoms, clinical signs or deaths were observed. The body weight of mice in chitosan group and control group showed no significant difference. Although HCS, COS and WSC had no significant effect on the level of Fe, Zn and Cu in the tested mice’s liver, spleen, heart and kidney, MCS significantly increased the level of Fe, Zn and Cu in liver. Therefore dietary ingestion of chitosan did not depress the level of Fe, Zn and Cu in mice.  相似文献   

12.
Serum copper and zinc levels were determined in 20 healthy women and in 100 women with gynecological tumors. Malignant and benign tumor cases were separated according to their postoperative, histopathological examinations. The stages of malignant and benign tumors were also established histologically. Seventy benign and 30 malignant genital tumors (carcinoma of cervix in situ, cervix, ovary endometrium, and vulva) of the patients were differentiated histopathologically. The serum Cu/Zn ratios of patients were increased significantly from the control group (0.32±0.35) to the benign group (1.22±0.63) and from the benign group to the malignant group (2.24±1.03). Nine of 30 malignant cases were determined as false negative (30%) and 15 of 70 benign cases were determined as false positive (14.2%) according to the serum Cu/Zn ratios of patients. Serum copper levels of 30 malignant and 10 benign tumor cases showed linear correlation with serum ceruloplasmin values.  相似文献   

13.
Interactions of micronutrients can affect absorption and bioavailability of other nutrients by a number of mechanisms. In aqueous solutions, and at higher uptake levels, competition between elements with similar chemical characteristics and uptake process can take place. The consequences of these interactions may depend on the relative concentrations of the nutrients. In this work, we measure the effects of increasing concentrations of iron, zinc, and copper on iron and copper uptake in Caco-2 cells. Intracellular Fe or Cu levels were affected by incubating with increased concentrations of metals. However, when the cells already had different intracellular metal concentration, the uptake of Fe or Cu was nor affected. In competition studies, we showed that Cu and Zn inhibited Fe uptake, and while Fe inhibited Cu uptake, Zn did not. When the three metals were given together (1:1:1 ratio), Fe or Cu uptake was inhibited approximately 40%. These results point to a potential risk in the absorption and bioavailability of these minerals by the presence of other minerals in the diet. This aspect must be considered in food supplementation and fortification programs.  相似文献   

14.
The present study was designed to investigate the effects of Zn administration on metallothionein concentrations in the liver, kidney, and intestine of copper-loaded rats. Male CD rats were fed a diet containing 12 mg Cu and 67 mg Zn/kg body wt. They were divided into either acute or chronic experimental protocols. Rats undergoing acute experiments received daily ip injections of either Cu (3 mg/kg body wt) or Zn (10 mg/kg body wt) for 3 d. Chronic experiments were carried out on rats receiving Cu ip injections on d 1, 2, 3, 10, 17, and 24, Cu injections plus a Zn-supplemented diet containing 5 g Zn/kg solid diet, or a Zn-supplemented diet alone. Rats injected Zn or Cu had increased MT concentrations in liver and kidney. Zn produced the most important effects and the liver was the most responsive organ. Rats fed a Zn-supplemented diet had significantly higher MT concentrations in liver and intestine with respect to controls. Increased MT synthesis in the liver may contribute to copper detoxification; the hypothesis of copper entrapment in enterocytes cannot be confirmed.  相似文献   

15.
The present study was designed to investigate the effect of mercuric chloride administration on copper, zinc, and iron concentrations in the liver, kidney, lung, heart, spleen, and muscle of rats. The results showed that after dose and time exposure to mercuric chloride, the concentration of mercury in the six tissues was significantly elevated. Data showed that there were no interaction between mercury and tissue iron. There was a considerable elevation of the content of copper in the kidney and liver. The most significant changes in the copper concentration took place in the kidneys. About a twofold increase in the copper content of the kidney was noted after exposure to mercuric chloride (3 mg and 5 mg/kg). Only slight elevations in the copper content occurred in the liver, especially in high dose and longer exposure time. In the remaining organs, the copper content was not changed significantly (p>0.05). The most significant changes in the zinc concentration took place in liver, kidney, lung, and heart (5 mg/kg). Marked changes in kidney zinc concentrations were observed at any of the specified doses. Zinc concentrations were significantly increased in kidney of rats sacrificed 9–48 h after sc injection of HgCl2 (5 mg/kg); in liver obtained from rats at 18, 24, or 48 h after injection; and in lung after 24 or 48 h of treatment. The heart and spleen zinc concentrations were elevated at 24 and 48 h after injection of HgCl2 (5 mg/kg), respectively. The results of this study implicate that effects on copper and zinc concentrations of the target tissues of mercury may play an important role in the pathogenesis of acute mercuric chloride intoxication.  相似文献   

16.
17.
In this report, we present the results of our investigations on the effect of Mg pretreatment on Cd and bioelements (Cu and Zn) contents in kidney of mice exposed to acute and subacute Cd intoxication. Acute intoxication was performed on male Swiss mice given a single oral dose of 20 mg Cd/kg body weight and mice given the same dose of Cd but pretreated with 40 mg Mg/kg body weight. For subacute intoxication one group of mice was given 10 mg Cd/kg body weight every day, for 2 wk, and the other one received the same dose of Cd after oral Mg intake of 20 mg/kg body weight. Cd, Cu, and Zn content was determined in kidney by atomic absorption spectrophotometry. In acute Cd intoxication, Mg pretreatment resulted in significant decrease of Cd in kidney after 4 and 6 h, compared with animals given only Cd. Under the condition of subacute Cd intoxication, Mg supplementation reduced Cd kidney content after 2 wk for about 30%, compared with animals treated with Cd only. The effect of Mg on Cu and Zn kidney content was also beneficial.  相似文献   

18.
The levels of iron, zinc, and copper in the tissues of the pregnant rat, on d 12, 19, and 21 after impregnation have been determined and compared with controls. Iron levels decreased considerably in late pregnancy as a result of increased fetal requirements, thus diminishing iron stores in rat tissues, but maintaining the circulating plasma levels. Copper levels increased slightly at midpregnancy, but returned to control levels at the end of gestation. Zinc stores also increased slightly during early pregnancy, yet were decreased at the end of pregnancy, but to a lesser extent than those of iron. The data are explained on the basis of equilibrium between assimilation and fetal needs for copper, a slightly higher demand for zinc with altered equilibrium, and a much altered equilibrium for iron that provokes a dwindling of iron maternal reserves that is not compensated by dietary iron.  相似文献   

19.
Chromium (Cr), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) concentrations were quantified in serum (n=112), milk (n=112), liver (n=70), and kidney samples (n=67) of dairy cows from an iron-steel processing region (Payas-Iskenderun) and from an area free of industrial pollution (Antakya) in Hatay, located in Southern Turkey. Samples were collected in the summer and winter and element determinations were carried out by inductively coupled plasma-atomic emission spectrometry. The mean concentrations of selected elements in serum were found to be similar in both regions. Milk samples collected from the nonindustrial region in the summer had higher Cr, Mn, and Zn concentrations than the polluted region. The liver Cu and kidney Mn levels of samples taken from the industrial region in winter were higher than samples of the unpolluted region. Copper and Fe concentrations in milk, Cr, Mn, Zn, and Fe levels in the liver, and Cr, Cu, Zn, and Fe levels in kidney samples were not found to be different among the regions in both seasons. Copper concentrations were below the critical level in the 25% of serum and 32% of liver samples analyzed in this study. Fifteen percent of serum samples and most of the liver samples had lower amounts of Zn than other reported studies. Although slight differences were observed between the industrial and nonindustrial regions, industrial activities and seasonal changes had no significant effect on selected element concentrations on cows and their milk.  相似文献   

20.
Biological Trace Element Research - Female guinea pigs were exposed to 10 doses of 3 mg/kg body weight of methylmercuric chloride with or without concomitant equimolar doses of sodium selenite....  相似文献   

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